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Table of Contents MPEG-2 Elementary Video Structure of an MPEG-2 program stream. Sequence headers Construction extensions Sequence Extension Construction Sequence Display Extension Construction Quant Matrix Extension Construction Copyright extension Construction Sequence Scalable Extension Construction Group of Pictures Construction Picture Display Extension Construction Picture Coding Extension Construction Picture Coding Extension Construction Macroblock

MPEG-2 Elementary Video

  - stream structure
  - Sequence headers
  - Sequence Extension
  - Sequence Display Extension
  - Quant Matrix Extension
  - Copyright extension
  - Sequence Scalable Extension
  - Group of Pictures
  - Picture headers
  - Picture Display Extension
  - Picture Coding Extension
  - Slice

The structure differs from that of MPEG-1 elementary video in terms of the possible extensions and, in the case of the TMPG encoder, the number of slices.

Structure of an MPEG-2 program stream.

<html> <table id="byte"> <tbody> <tr> <td id="Col70">Sequence</td> <td id="Col70">Sequence</td> <td id="Col70">...</td> <td id="col70">Sequence</td> </tr> </tbody> </table>   The video stream consists of several consecutive sequences.   <h3>Sequence:</h3> <table id="byte"> <tbody> <tr> <td id="Col70">Sequence start code</td> <td id="Col70">video parameters</td> <td id="Col70">bitstream parameters</td> <td id="Col70">QT's, Misc</td> <td id="Col70">Group of Picture</td> <td id="Col70">...</td> <td id="Col70">Group of Picture</td> <td id="Col70">Sequence end code</td> </tr> </tbody> </table>   The sequence can or should contain further sequence headers. Usually before each Group of Picture (GOP). The sequence headers are needed for creating entry points (chapter markers) and for fast scrolling. At the end there should be a sequence decode. However, this does not seem to be common with MPEG-2.   <h3>Group of Picture (GOP):</h3> <table id="byte"> <tbody> <tr> <td id="Col70">GOP start code</td> <td id="Col70">timecode _</td> <td id="Col70">GOP params</td> <td id="Col70">Picture</td> <td id="Col70">...</td> <td id="Col70">Picture</td> </tr> </tbody> </table>   The GOP contains the different picture types. There are I, P, B and D frames. Intra picture (I-frames) are full images. Predicted picture (P frames) are partial pictures and refer to the previous I/P frames. Bidirectional pictures (B frames) are also partial pictures and refer to the preceding and following I/B frame. Direct Coded Picture (D-Frames) are not used in MPEG-2.   <h3>Picture:</h3> <table id="byte"> <tbody> <tr> <td id="Col70">Picture start code</td> <td id="Col70">Type</td> <td id="Col70">buffer params</td> <td id="Col70">Encode Params</td> <td id="Col70">Slice</td> <td id="Col70">...</td> <td id="Col70">Slice</td> </tr> </tbody> </table>   The order of the images does not correspond to the order in which they are displayed. The images are composed of slices.   <h3>Slice:</h3> <table id="byte"> <tbody> <tr> <td id="Col70">Slice start code</td> <td id="Col70">Vertical position</td> <td id="Col70">QScale</td> <td id="Col70">macro block</td> <td id="Col70">...</td> <td id="Col70">macro block</td> </tr> </tbody> </table>   Slices are a vertical and horizontal aggregation of macroblocks.   <h3>macro block:</h3> <table id="byte"> <tbody> <tr> <td id="Col70">Address Increment</td> <td id="Col70">Type</td> <td id="Col70">Motion Vector</td> <td id="Col70">QScale</td> <td id="Col70">CBP</td> <td id="Col70">b0</td> <td id="Col70">...</td> <td id="Col70">b5</td> </tr> </tbody> </table>   A macroblock comprises an image section with a total of 16x16 picture elements (pixels). It stores the YUV 4:2:0 (YCbCr) color information. The Y components of all pixels are contained in the first four blocks b0 to b3. In the fifth block b4, the blue chrominance values &ZeroWidthSpace;&ZeroWidthSpace;(Cb) are stored in one point for each 4 pixels. The corresponding red chrominance values &ZeroWidthSpace;&ZeroWidthSpace;(Cr) are in the sixth block b5. </html>

Sequence headers

Each header starts with the PACK_START_CODE_PREFIX, which consists of the three bytes 0, 0 and 1. As a hexadecimal number, it is represented as $000001. This is followed by the ID. For the sequence header, this is the value $B3. The length of the header has different lengths according to the matrices used.

Each sequence header represents a possible entry point. This means that a chapter can only be created where there is a sequence header.

It should also happen that sequence headers are not marked with $000001B3 but with $000000B3.

Construction

  - 4 bytes: SEQUENCE_HEADER_CODE = $000001B3
  - 12 Bit: Width - Image width in pixels
  - 12 Bit: Height - image height in pixels
  - 4 bit: Aspect Ratio - aspect ratio
  - 4 bit: frame rate - refresh rate
  - 18 bit: bit rate
  - 1 bit: markers
  - 10 bits: VBV
  - 1 bit: Constrained parameter flag
  - 1 bit: load intra matrix (0) or standard (1)?
  - 64 bytes: Intra matrix if non-standard matrix is used.
  - 1 Bit: Load Non Intra Matrix (0) or Standard (1)?
  - 64 bytes: Non Intra Matrix, unless Standard Matrix is used.

As a scheme:

<html> <div id="Inhalt"> <table id="byte"> <tbody> <tr valign="middle" align="center"> <td id="Col60"> </td> <td id="Col60">7</td> <td id="Col60">6</td> <td id="Col60">5</td> <td id="Col60">4</td> <td id="Col60">3</td> <td id="Col60">2</td> <td id="Col60">1</td> <td id="Col60">0</td> </tr> <tr valign="middle" align="center"> <td id="Col60">0</td> <td id="Col60" rowspan="4" colspan="8">SEQUENCE_HEADER_CODE</td> </tr> <tr valign="middle" align="center"> <td id="Col60">1</td> </tr> <tr valign="middle" align="center"> <td id="Col60">2</td> </tr> <tr valign="middle" align="center"> <td id="Col60">3</td> </tr> <tr valign="middle" align="center"> <td id="Col60">4</td> <td id="Col60" colspan="8">image width</td> </tr> <tr valign="middle" align="center"> <td id="Col60">5</td> <td id="Col60" colspan="4">nor image width</td> <td id="Col60" colspan="4">image height</td> </tr> <tr valign="middle" align="center"> <td id="Col60">6</td> <td id="Col60" colspan="12">nor image height</td> </tr> <tr valign="middle" align="center"> <td id="Col60">7</td> <td id="Col60" colspan="4">aspect ratio</td> <td id="Col60" colspan="4">frame rate</td> </tr> <tr valign="middle" align="center"> <td id="Col60">8th</td> <td id="Col60" colspan="8">bitrate</td> </tr> <tr valign="middle" align="center"> <td id="Col60">9</td> <td id="Col60" colspan="8">nor bitrate</td> </tr> <tr valign="middle" align="center"> <td id="Col60">10</td> <td id="Col60" colspan="2">nor bitrate</td> <td id="Col60">marker</td> <td id="Col60" colspan="5">VBV</td> </tr> <tr valign="middle" align="center"> <td id="Col60">11</td> <td id="Col60" colspan="5">VBV</td> <td id="Col60">CPF</td> <td id="Col60">Load?</td> <td id="Col60">IN THE</td> </tr> <tr valign="middle" align="center"> <td id="Col60">12</td> <td id="Col60" rowspan="2" colspan="8">still intra matrix</td> </tr> <tr valign="middle" align="center"> <td id="Col60">...</td> </tr> <tr valign="middle" align="center"> <td id="Col60">75</td> <td id="Col60" colspan="7">still intra matrix</td> <td id="Col60">Load?</td> </tr> <tr valign="middle" align="center"> <td id="Col60">76</td> <td id="Col60" rowspan="3" colspan="8">Non intra matrix</td> </tr> <tr valign="middle" align="center"> <td id="Col60">...</td> </tr> <tr valign="middle" align="center"> <td id="Col60">139</td> </tr> </tbody> </table>   The MPEG type can only be taken directly from the sequence header if the aspect ratio has a value above 4. But then it is an MPEG-1 video.   <h2>Explanations</h2> The values &ZeroWidthSpace;&ZeroWidthSpace;for the aspect ratio: <table id="sheme"> <tbody> <tr> <td>value</td> <td>Aspect ratio text</td> </tr> <tr> <td>0</td> <td>'forbidden'</td> </tr> <tr> <td>1</td> <td>1:1 square pixels</td> </tr> <tr> <td>2</td> <td>4:3 screen</td> </tr> <tr> <td>3</td> <td>16:9 screen</td> </tr> <tr> <td>4</td> <td>2.21:1 display</td> </tr> <tr> <td>5-15</td> <td>'reserved'</td> </tr> </tbody> </table>   The values &ZeroWidthSpace;&ZeroWidthSpace;for the frame rate (refresh rate): <table id="sheme"> <tbody> <tr> <td>value</td> <td>Frame rate number</td> <td>Frame rate text</td> </tr> <tr> <td>0</td> <td>0</td> <td>'forbidden'</td> </tr> <tr> <td>1</td> <td>24000/1001.0</td> <td>'23.976 fps -- NTSC encapsulated film rate'</td> </tr> <tr> <td>2</td> <td>24.0</td> <td>'Standard international cinema film rate'</td> </tr> <tr> <td>3</td> <td>25.0</td> <td>'PAL (625/50) video frame rate'</td> </tr> <tr> <td>4</td> <td>30000/1001.0</td> <td>'29.97 -- NTSC video frame rate'</td> </tr> <tr> <td>5</td> <td>30.0</td> <td>'NTSC drop-frame (525/60) video frame rate'</td> </tr> <tr> <td>6</td> <td>50.0</td> <td>'double frame rate/progressive PAL'</td> </tr> <tr> <td>7</td> <td>60000/1001.0</td> <td>'double frame rate NTSC'</td> </tr> <tr> <td>8th</td> <td>60.0</td> <td>'double frame rate drop frame NTSC'</td> </tr> <tr> <td>9-15</td> <td>0</td> <td>'reserved'</td> </tr> </tbody> </table> </div> </html>

The bit rate is given in 400 bits per second. The value $3FFFF is supposed to mean a variable bitrate. In the test, TMPGEnc and CCEB each indicated the maximum bit rate there.

The marker bit is intended to detect errors. It must always have the value 1.

The VBV is the memory required to decode the images. It is specified in 16 kB blocks.

The constrained parameter flag is always set to 0 here. The TMPG Encoder 2.5* uses the 10 bits for the VBV and the bit of the constrained parameter flag for the VBV specification, so that only half of the VBV is displayed here.

The intra or non intra matrix load bit indicates whether the standard matrix is used or whether the corresponding matrix is saved at this point and must be loaded. The matrix is stored in Zig Zag Scan.

extensions

At least one extension follows the sequence header. An MPEG-2 is identified via this. The ID of the extension is $B5. This is followed by the ID of the extension. These extensions should be considered for the sequence header:

  - Sequence Extension
  - Sequence Display Extension
  - Quant Matrix Extension
  - Copyright Extension
  - Sequence Scalable Extension

Sequence Extension

Extensions have the ID $B5. This is followed by the ID of the extension, here $1.

Construction

  - 4 bytes: EXTENSION_START_CODE = $000001B5
  - 4 bits: Start Code Identifier - Sequence Extension = $1
  - 4 bit: profile
  - 4 bits: levels
  - 1 bit: progressive sequence
  - 2-bit: chroma format
  - 2 bit: wide extension
  - 2 bits: height extension
  - 12-bit: bit rate extension
  - 1 bit: markers
  - 8-bit: VBV Buffer Extension
  - 1 bit: low delay
  - 2 bits: Frame rate extension numerator
  - 5 bits: Frame rate extension denominator

As a scheme:

<html> <div id="Inhalt"> <table id="byte"> <tbody> <tr valign="middle" align="center"> <td id="Col60"> </td> <td id="Col60">7</td> <td id="Col60">6</td> <td id="Col60">5</td> <td id="Col60">4</td> <td id="Col60">3</td> <td id="Col60">2</td> <td id="Col60">1</td> <td id="Col60">0</td> </tr> <tr valign="middle" align="center"> <td id="Col60">0</td> <td id="Col60" rowspan="4" colspan="8">EXTENSION_START_CODE   $000001B5</td> </tr> <tr valign="middle" align="center"> <td id="Col60">1</td> </tr> <tr valign="middle" align="center"> <td id="Col60">2</td> </tr> <tr valign="middle" align="center"> <td id="Col60">3</td> </tr> <tr valign="middle" align="center"> <td id="Col60">4</td> <td id="Col60" colspan="4">Boot Code Identifier = $1</td> <td id="Col60" colspan="4">profile</td> </tr> <tr valign="middle" align="center"> <td id="Col60">5</td> <td id="Col60" colspan="4">levels</td> <td id="Col60">program</td> <td id="Col60" colspan="2">chroma</td> <td id="Col60">width ext.</td> </tr> <tr valign="middle" align="center"> <td id="Col60">6</td> <td id="Col60">still BE.</td> <td id="Col60" colspan="2">height ext.</td> <td id="Col60" colspan="5">Bit Rate Extension</td> </tr> <tr valign="middle" align="center"> <td id="Col60">7</td> <td id="Col60" colspan="7">nor bit rate extension</td> <td id="Col60">marker</td> </tr> <tr valign="middle" align="center"> <td id="Col60">8th</td> <td id="Col60" colspan="8">VBV Buffer Extension</td> </tr> <tr valign="middle" align="center"> <td id="Col60">9</td> <td id="Col60">Low Delay</td> <td id="Col60" colspan="2">Framerate Ext N</td> <td id="Col60" colspan="5">Framerate Ext D</td> </tr> </tbody> </table>   Note: In a source, four bits are used for the profile. In Andrew Duncan, the first bit of this is called 'Profile/Level Escape', with the value 0 being reserved. <h2>Explanations</h2> The profiles are: <table id="sheme"> <tbody> <tr> <td>value</td> <td>profile</td> <td>Typical for</td> </tr> <tr> <td>1</td> <td>High profile</td> <td>production equipment requiring 4:2:2</td> </tr> <tr> <td>2</td> <td>Spatially Scalable Profile</td> <td>simulcasting</td> </tr> <tr> <td>3</td> <td>SNR Scalable Profile</td> <td>simulcasting</td> </tr> <tr> <td>4</td> <td>Main profiles</td> <td>95% of TVs, VCRs, cable applications</td> </tr> <tr> <td>5</td> <td>Simple profiles</td> <td>Low-cost memory, eg no B pictures</td> </tr> </tbody> </table>   The profiles Multiview and 4:2:2 are sometimes also specified, but without coding. The levels are: <table id="sheme"> <tbody> <tr> <td>value</td> <td>profile</td> <td>Typical for</td> </tr> <tr> <td>4</td> <td>high level</td> <td>HDTV production rates: e.g. 1920 x 1080 x 30 Hz</td> </tr> <tr> <td>6</td> <td>High 1440 levels</td> <td>HDTV consumer rates: e.g. 1440 x 960 x 30 Hz</td> </tr> <tr> <td>8th</td> <td>main level</td> <td>CCIR 601 rates: eg 720 x 480 x 30 Hz</td> </tr> <tr> <td>10</td> <td>low level</td> <td>SIF video rate: e.g. 352 x 240 x 30 Hz</td> </tr> </tbody> </table>   Allowed combinations of level and profile: <table id="sheme"> <tbody> <tr align="center"> <td> </td> <td>Simple</td> <td>Main</td> <td>SNR scalable</td> <td>Spatially scalable</td> <td>High</td> <td>multiview</td> <td>4:2:2</td> </tr> <tr align="center"> <td align="left">high level</td> <td> </td> <td>X</td> <td> </td> <td> </td> <td>X</td> <td> </td> <td> </td> </tr> <tr align="center"> <td align="left">High-1440 level</td> <td> </td> <td>X</td> <td> </td> <td>X</td> <td>X</td> <td> </td> <td> </td> </tr> <tr align="center"> <td align="left">main level</td> <td>X</td> <td>X</td> <td>X</td> <td> </td> <td>X</td> <td>X</td> <td>X</td> </tr> <tr align="center"> <td align="left">low level</td> <td> </td> <td>X</td> <td>X</td> <td> </td> <td> </td> <td> </td> <td> </td> </tr> </tbody> </table>   The chrominance values: <table id="sheme"> <tbody> <tr> <td>value</td> <td>profile</td> <td>description</td> </tr> <tr> <td>1</td> <td>4:2:0</td> <td>half resolution in both dimensions (most common format)</td> </tr> <tr> <td>2</td> <td>4:2:2</td> <td>Half resolution in horizontal direction (High Profile only)</td> </tr> <tr> <td>3</td> <td>4:4:4</td> <td>full resolution (not allowed in any currently defined profile)</td> </tr> </tbody> </table>   Low Delay means that no B-frames are used. "Frame reordering delay is not present i the VBV description, skipped pictures (VBV underflow) may occur." The Framerate Extension Numerator and Denominator are multiplied by the base framerate.   </div> </html>

Sequence Display Extension

Extensionen are ID $B5. The ID is $2.

Construction

4 Byte: EXTENSION_START_CODE = $000001B5

4 Bit: Start Code Identifier - Sequence Display Extension = $2

3 Bit: Video Format

1 Bit: Color, if set:

  - 1 Byte: Color Primaries
  - 1 Byte: Transfer Characteristics
  - 1 Byte: Matrix Coefficients

14 Bit: Display Width

1 Bit: Marker

14 Bit: Display Height

As a scheme:

 <html>
    <table id="byte"> 
     <tbody>
      <tr height="26" valign="middle" align="center"> 
       <td id="Col60">&nbsp;</td> 
       <td id="Col00060">7</td> 
       <td id="Col60">6</td> 
       <td id="Col60">5</td> 
       <td id="Col60">4</td> 
       <td id="Col60">3</td> 
       <td id="Col60">2</td> 
       <td id="Col60">1</td> 
       <td id="Col60">0</td> 
      </tr> 
      <tr height="26" valign="middle" align="center"> 
       <td id="Col60">0</td> 
       <td id="Col60" rowspan="4" colspan="8">EXTENSION_START_CODE<br>&nbsp;<br>$000001B5</td> 
      </tr> 
      <tr height="26" valign="middle" align="center"> 
       <td id="Col60">1</td> 
      </tr> 
      <tr height="26" valign="middle" align="center"> 
       <td id="Col60">2</td> 
      </tr> 
      <tr height="26" valign="middle" align="center"> 
       <td id="Col60">3</td> 
      </tr> 
      <tr height="26" valign="middle" align="center"> 
       <td id="Col60">4</td> 
       <td id="Col60" colspan="4">Start Code Identifier = $2</td> 
       <td id="Col60" colspan="3">Video Format</td> 
       <td id="Col60">Color</td> 
      </tr> 
      <tr height="26" valign="middle" align="center"> 
       <td id="Col60"><font class="fb">5</font></td> 
       <td id="Col60" colspan="8"><font class="fb">Color Primaries</font></td> 
      </tr> 
      <tr height="26" valign="middle" align="center"> 
       <td id="Col60"><font class="fb">6</font></td> 
       <td id="Col60" colspan="8"><font class="fb">Transfer Characteristics</font></td> 
      </tr> 
      <tr height="26" valign="middle" align="center"> 
       <td id="Col60"><font class="fb">7</font></td> 
       <td id="Col60" colspan="8"><font class="fb">Matrix Coefficients</font></td> 
      </tr> 
      <tr height="26" valign="middle" align="center"> 
       <td id="Col60">5 / <font class="fb">8</font></td> 
       <td id="Col60" colspan="8">Display Width</td> 
      </tr> 
      <tr height="26" valign="middle" align="center"> 
       <td id="Col60">6 / <font class="fb">9</font></td> 
       <td id="Col60" colspan="6">Display Width</td> 
       <td id="Col60">Marker</td> 
       <td id="Col60">D H</td> 
      </tr> 
      <tr height="26" valign="middle" align="center"> 
       <td id="Col60">7 / <font class="fb">10</font></td> 
       <td id="Col60" colspan="8">Display Height</td> 
      </tr> 
      <tr height="26" valign="middle" align="center"> 
       <td id="Col60">8 / <font class="fb">11</font></td> 
       <td id="Col60" colspan="5">Display Height</td> 
       <td id="Col60" colspan="3">...</td> 
      </tr> 
     </tbody>
    </table> 
    <p>&nbsp;</p> 
    <h2>Explainations</h2> 
    <p>Video Formats are:</p> 
    <table id="sheme"> 
     <tbody>
      <tr height="20"> 
       <td width="60">Value</td> 
       <td width="240">Format</td> 
      </tr> 
      <tr height="20"> 
       <td>0</td> 
       <td>Component</td> 
      </tr> 
      <tr height="20"> 
       <td>1</td> 
       <td>PAL</td> 
      </tr> 
      <tr height="20"> 
       <td>2</td> 
       <td>NTSC</td> 
      </tr> 
      <tr height="20"> 
       <td>3</td> 
       <td>SECAM</td> 
      </tr> 
      <tr height="20"> 
       <td>4</td> 
       <td>MAC</td> 
      </tr> 
      <tr height="20"> 
       <td>5-8</td> 
       <td>Reserved</td> 
      </tr> 
     </tbody>
    </table> 
    <p>&nbsp;</p> 
    <p>Color Primaries and Transfer Characteristics are:</p> 
    <table id="sheme"> 
     <tbody>
      <tr height="20"> 
       <td width="60">Wert</td> 
       <td width="240">Profil</td> 
      </tr> 
      <tr height="20"> 
       <td>0</td> 
       <td>Forbidden</td> 
      </tr> 
      <tr> 
       <td>1</td> 
       <td>ITU-R Rec. 709 (1990)</td> 
      </tr> 
      <tr> 
       <td>2</td> 
       <td>Unspecified</td> 
      </tr> 
      <tr> 
       <td>3</td> 
       <td>Reserviert</td> 
      </tr> 
      <tr> 
       <td>4</td> 
       <td>ITU-R Rec. 624-4 System M</td> 
      </tr> 
      <tr> 
       <td>5</td> 
       <td>ITU-R Rec. 624-4 System B, G</td> 
      </tr> 
      <tr> 
       <td>6</td> 
       <td>SMPTE 170M</td> 
      </tr> 
      <tr> 
       <td>7</td> 
       <td>SMPTE 240M (1987)</td> 
      </tr> 
      <tr> 
       <td>...</td> 
       <td>Reserviert</td> 
      </tr> 
     </tbody>
    </table> 
    <p>&nbsp;</p> 
    <p>Matrix Coefficients:</p> 
    <table id="sheme"> 
     <tbody>
      <tr height="20"> 
       <td width="60">Value</td> 
       <td width="240">Profile</td> 
      </tr> 
      <tr height="20"> 
       <td>0</td> 
       <td>Forbidden</td> 
      </tr> 
      <tr height="20"> 
       <td>1</td> 
       <td>ITU-R Rec. 709 (1990)</td> 
      </tr> 
      <tr height="20"> 
       <td>2</td> 
       <td>Unspecified</td> 
      </tr> 
      <tr height="20"> 
       <td>3</td> 
       <td>Reserved</td> 
      </tr> 
      <tr height="20"> 
       <td>4</td> 
       <td>FCC</td> 
      </tr> 
      <tr height="20"> 
       <td>5</td> 
       <td>ITU-R Rec. 624-4 System B, G</td> 
      </tr> 
      <tr height="20"> 
       <td>6</td> 
       <td>SMPTE 170M</td> 
      </tr> 
      <tr height="20"> 
       <td>7</td> 
       <td>SMPTE 240M (1987)</td> 
      </tr> 
      <tr height="20"> 
       <td>...</td> 
       <td>Reserved</td> 
      </tr> 
     </tbody>
    </table> 
 </html>

Quant Matrix Extension

Extensions have the ID $B5. The ID of this extension is $3.

Construction

4 bytes: EXTENSION_START_CODE = $000001B5

4 bits: Start Code Identifier - Quant Matrix Extension = $3

1 bit: Load Intra Quantiser Matrix, if 1 then

  * 64 bytes: intra quantizer matrix

1 Bit: Load Non Intra Quantiser Matrix, if 1 then

  * 64 bytes: non-intra quantiser matrix

1 bit: Load Chroma Intra Quantiser Matrix if 1 then

  * 64 bytes: Chroma Intra Quantizer Matrix

1 bit: Chroma Non Intra Quantiser Matrix, if 1 then

  * 64 bytes: Chroma Non Intra Quantizer Matrix

As a scheme:

<html> <table id="byte"> <tbody><tr><td> </td><td>7</td><td>6</td><td>5</td><td>4</td><td>3</td><td>2</td><td>1</td><td>0</td></tr> <tr><td>0</td><td rowspan="4" colspan="8">EXTENSION_START_CODE   $000001B5</td></tr> <tr><td>1</td></tr> <tr><td>2</td></tr> <tr><td>3</td></tr> <tr><td>4</td><td colspan="4">Boot Code Identifier = $3</td><td>Load?</td><td colspan="3">Intra Quantizer Matrix</td></tr> <tr><td>5-67</td><td colspan="8">Intra Quantizer Matrix</td></tr> <tr><td>68</td><td colspan="5">Intra Quantizer Matrix</td><td>Load?</td><td colspan="2">NIQM</td></tr> <tr><td>69-131</td><td colspan="8">Non Intra Quantizer Matrix</td></tr> <tr><td>132</td> <td colspan="6">Non Intra Quantizer Matrix</td><td>Load?</td><td>CIQM</td></tr> <tr><td>133-195</td><td colspan="8">Chroma Intra Quantizer Matrix</td></tr> <tr><td>196</td><td colspan="7">Chroma Intra Quantizer Matrix</td><td>Load?</td></tr> <tr><td>197-260</td><td colspan="8">Chroma Non Intra Quantizer Matrix</td></tr> </tbody></table> </html>

Copyright extension

Extensions have the ID $B5. This extension has the ID $4.

Construction

<html> <h3>As a scheme:</h3> <table id="byte"> <tbody><tr><td> </td><td>7</td><td>6</td><td>5</td><td>4</td><td>3</td><td>2</td><td>1</td><td>0</td></tr> <tr><td>0</td><td rowspan="4" colspan="8">EXTENSION_START_CODE   $000001B5</td></tr> <tr><td>1</td></tr> <tr><td>2</td></tr> <tr><td>3</td></tr> <tr><td>4</td><td colspan="4">Boot Code Identifier = $4</td><td>copyright flag</td><td colspan="3">copyright identifiers</td></tr> <tr><td>5</td><td colspan="5">nor copyright identifiers</td><td>copy?</td><td colspan="2">reserved</td></tr> <tr><td>6</td><td colspan="5">reserved</td><td>marker</td><td colspan="2">CN 1</td></tr> <tr><td>7</td><td colspan="8">nor copyright number 1</td></tr> <tr><td>8th</td><td colspan="8">nor copyright number 1</td></tr> <tr><td>9</td><td colspan="2">still CN 1</td><td>marker</td><td colspan="5">Copyright number 2</td></tr> <tr><td>10</td><td colspan="8">nor copyright number 2</td></tr> <tr><td>11</td><td colspan="8">nor copyright number 2</td></tr> <tr><td>12</td><td>still CN 2</td><td>marker</td><td colspan="6">Copyright number 3</td></tr> <tr><td>13</td><td colspan="8">nor copyright number 3</td></tr> <tr><td>14</td><td colspan="8">nor copyright number 3</td></tr> </tbody></table> </html>

Sequence Scalable Extension

Extensions generally have ID $B5. This extensions has got ID $5.

Construction

  * 4 Byte: EXTENSION_START_CODE = $000001B5
  * 4 Bit: Start Code Identifier - Sequence Scalable Extension = $5
  * 2 Bit: Scalable Mode (Data partioning, Spartial, SNR, Temporal)
  * 4 Bit: Layer ID

Ist der Scalable Mode "spatial scalability"

  * 14 Bit: Lower Layer Prediction Horizontal Size
  * 1 Bit: Marker
  * 14 Bit: Lower Layer Prediction Vertical Size
  * 5 Bit: Horizontal Subsampling Factor M
  * 5 Bit: Horizontal Subsampling Factor N
  * 5 Bit: Vertical Subsampling Factor M
  * 5 Bit: Vertical Subsampling Factor N

Ist der Scalable Mode "temporal scalability"

1 Bit: Picture Mux Enable, if 1 then

  * 1 Bit: Mux To Progressive Sequence

3 Bit: Picture Mux Order

3 Bit: Picture Mux Factor

<html> <content> <h3>As a scheme:</h3> <table id="byte"> <tbody><tr><td>&nbsp;</td><td>7</td><td>6</td><td>5</td><td>4</td><td>3</td><td>2</td><td>1</td><td>0</td></tr> <tr><td>0</td><td rowspan="4" colspan="8">EXTENSION_START_CODE &nbsp; $000001B5</td></tr> <tr><td>1</td></tr> <tr><td>2</td></tr> <tr><td>3</td></tr> <tr><td>4</td><td colspan="4">Start Code Identifier = $5</td><td colspan="2">Scalable Mode</td><td colspan="2">Layer ID</td></tr> <tr><td>5</td><td colspan="2">still Layer ID</td><td colspan="6">&nbsp;</td></tr> </tbody></table> Scalable Mode = "spatial scalability": <table id="byte"> <tbody><tr><td>&nbsp;</td><td>7</td><td>6</td><td>5</td><td>4</td><td>3</td><td>2</td><td>1</td><td>0</td></tr> <tr><td>5</td><td colspan="2">&nbsp;</td><td colspan="6">Lower Layer Prediction Horizontal Size</td></tr> <tr><td>6</td><td colspan="8">noch Lower Layer Prediction Horizontal Size</td></tr> <tr><td>7</td><td>Marker</td><td colspan="7">Lower Layer Prediction Vertical Size</td></tr> <tr><td>8</td><td colspan="7">noch Lower Layer Prediction Vertical Size</td><td>HSF M</td></tr> <tr><td>9</td><td colspan="4">noch Horizontal Subsampling Factor M</td><td colspan="4">Horizontal Subsampling Factor N</td></tr> <tr><td>10</td><td>n. HSF N</td><td colspan="5">Vertical Subsampling Factor M</td><td colspan="2">VSF N</td></tr> <tr><td>11</td><td colspan="3">noch Vertical Subsampling Factor N</td><td colspan="5">&nbsp;</td></tr> </tbody></table> Scalable Mode = "temporal scalability": <table id="byte"> <tbody><tr><td>&nbsp;</td><td>7</td><td>6</td><td>5</td><td>4</td><td>3</td><td>2</td><td>1</td><td>0</td></tr> <tr><td>5</td><td colspan="2">&nbsp;</td><td>Picture Mux Enable</td><td>Mux to Progr. Sequence</td><td colspan="3">Picture Mux Order</td><td>PMF</td></tr> <tr><td>6</td><td colspan="2">noch Picture Mux Faktor</td><td colspan="6">&nbsp;</td></tr> </tbody></table> </content> </html>

Group of Pictures

The ID $B8 follows the PACK_START_CODE_PREFIX for the GROUP_START_CODE. The length of the header is 4 bytes.

Construction

  * 4 bytes: GROUP_START_CODE = $000001B8
  * 1 bit: drop frame
  * 5 bit: Time code hours from 0 to 23.
  * 6 bit: Time code minutes from 0 to 59.
  * 1 bit: markers
  * 6 bit: Time Code seconds from 0 to 59.
  * 6 bit: Time Code Picture from 0 to 59.
  * 1 bit: Closed GOP
  * 1 bit: broken link

As a scheme:

<html> <content> <table id="byte"> <tbody><tr><td>&nbsp;</td><td>7</td><td>6</td><td>5</td><td>4</td><td>3</td><td>2</td><td>1</td><td>0</td></tr> <tr><td>0</td><td rowspan="4" colspan="8">GROUP_START_CODE</td></tr> <tr><td>1</td></tr> <tr><td>2</td></tr> <tr><td>3</td></tr> <tr><td>4</td><td>Drop frame</td><td colspan="5">Time code hours</td><td colspan="2">Time code minutes</td></tr> <tr><td>5</td><td colspan="4">still time code minutes</td><td>marker</td><td colspan="3">Time code seconds</td></tr> <tr><td>6</td><td colspan="3">still time code seconds</td><td colspan="5">Time Code Picture</td></tr> <tr><td>7</td><td>nor TCP</td><td>Closed GOP</td><td>broken link</td><td colspan="5">&nbsp;</td></tr> </tbody></table> <h2>Explanations</h2> The drop frame is used for NTSC to lower the frame rate from 30 to 29.97 fps. The marker must again be set. A GOP is closed if the pictures in a GOP relate only to pictures in its own GOP. Even if the stream is not encdet closed, the first and penultimate (CCE Basic) or last (TMPG Encoder) GOP are closed. The broken link flag is set when frames refer to frames that no longer exist after a cut. </content> </html> <html> <content> <h1>Picture Header</h1> PACK_START_CODE_PREFIX follows PICTURE_START_CODE with ID $00. <h2>Construction</h2> <ul> <li>4 Byte: PICTURE_START_CODE = $00000100</li> <li>10 Bit: Temporal Reference</li> <li>3 Bit: Coding Type</li> <li>16 Bit: VBV Delay.</li> </ul> P- and B-Frames: <ul> <li>1 Bit: full fel forward vector</li> <li>3 Bit: forward f code</li> </ul> B-Frames only: <ul> <li>1 Bit: full backward vector</li> <li>3 Bit: backward f code</li> </ul> Extra Information: <ul> <li>1 Bit: Extra Info Bit Set</li> <li>1 Byte: Extra Information, if Extra Bit is set.</li> <li>1 Bit: Extra Info Bit cleared</li> </ul> <h3>Als Schema</h3> <table id="byte"> <tbody><tr><td>&nbsp;</td><td>7</td><td>6</td><td>5</td><td>4</td><td>3</td><td>2</td><td>1</td><td>0</td></tr> <tr><td>0</td><td rowspan="4" colspan="8">PICTURE_START_CODE</td></tr> <tr><td>1</td></tr> <tr><td>2</td></tr> <tr><td>3</td></tr> <tr><td>4</td><td colspan="8">Temporal Reference</td></tr> <tr><td>5</td><td colspan="2">Temporal Reference</td><td colspan="3">Coding Type</td><td colspan="3">VBV Delay</td></tr> <tr><td>6</td><td colspan="8">noch VBV Delay</td></tr> <tr><td>7</td><td colspan="5">noch VBV Delay</td><td>full fel forward vector</td><td colspan="2">forward f code</td></tr> <tr><td>8</td><td>noch forward f code</td><td>full backward vector</td><td colspan="3">backward f code</td><td>Extra Bit set</td><td colspan="2">Extra Information</td></tr> <tr><td>9</td><td colspan="6">Noch Extra Information</td><td>...</td><td>Extra Bit cleared</td></tr> </tbody></table> <h2>Erläuterungen</h2> The temporal reference is the order in which the images should be displayed. The first picture of the group has the value 0. Coding types: <ul start="0"> <li>Resticted</li> <li>I - Intra Coded</li> <li>P - Predictive Coded</li> <li>B - Bidirectionally Predictive Coded</li> <li>D - DC Intra Coded</li> <li>Reserved</li> <li>Reserved</li> <li>Reserved</li> </ul> The VBV delay is specified in 90 kHz cycles at constant bit rates. With variable bit rate, the delay is set to FFFF. I am missing further information about the forward and backward vectors and the extra information. The extra information consists of nine bits. The first is the indicator for extra information to follow. The following 8 bits represent the extra information. <h1>Extensions</h1> With MPEG-2, the picture header is followed by various extensions. The ID of the extension is $B5. That concludes the ID of the extension. These extensions should be considered for the picture header: <ul> <li>7 - <a href="projects/mpeg/k010210.htm">Picture Display Extension</a></li> <li>8 - <a href="projects/mpeg/k010211.htm">Picture Coding Extension</a></li> <li>9 - Picture Spatial Scalable Extension</li> <li>10 - Picture Temporal Scalable Extension</li> </ul> </content> </html>

Picture Display Extension

The extension start code with the ID $B5 is followed by four bits with the extension ID $B7.

Construction

  * 4 bytes: EXTENSION_START_CODE = $000001B5
  * 4 bits: Start Code Identifier - Picture Display Extension = $7
  * For 0 = i < number_of_frame_centre_offsets (maximum 3 offsets)
    * 2 bytes (Int16): frame_centre_horizontal_offset
    * 1 bit: markers
    * 2 bytes (Int16): frame_centre_vertical_offset
    * 1 bit: markers

As a scheme:

<html> <content> <table id="byte"> <tbody><tr><td>&nbsp;</td><td>7</td><td>6</td><td>5</td><td>4</td><td>3</td><td>2</td><td>1</td><td>0</td></tr> <tr><td>0</td><td rowspan="4" colspan="8">EXTENSION_START_CODE &nbsp; $000001B5</td></tr> <tr><td>1</td></tr> <tr><td>2</td></tr> <tr><td>3</td></tr> <tr><td>4</td><td colspan="4">Boot Code Identifier = $7</td><td colspan="4">frame_centre_horizontal_offset</td></tr> <tr><td>5</td><td colspan="8">nor frame_centre_horizontal_offset</td></tr> <tr><td>6</td><td colspan="4">nor frame_centre_horizontal_offset</td><td>marker</td><td colspan="3">frame_centre_vertical_offset</td></tr> <tr><td>7</td><td colspan="8">nor frame_centre_vertical_offset</td></tr> <tr><td>8th</td><td colspan="5">nor frame_centre_vertical_offset</td><td>marker</td><td colspan="2">...</td></tr> </tbody></table> <h2>Explanations</h2> This extension is not necessary for the normal decoding process. However, it allows the picture to be positioned on the display. An application for this is <a href="https://web.archive.org/web/20200805111659/http://de.wikipedia.org/wiki/Pan_&amp;amp;_Scan" target="_blank">Pan &amp; Scan</a> . This extension must be preceded by a sequence display extension. frame_centre_horizontal_offset Is the horizontal offset in units of 1/16 sample. A positive value means the center of the picture is to the right of the center of the display. frame_centre_vertical_offset Is the vertical offset in units of 1/16 sample. A positive value means the center of the picture is below the center of the display. The size of the display is defined in the Sequence Display Extension. The coordinates for the decoded picture in the picture display extension. The center of the decoded picture is the center of the display. A picture can refer to one, two or three decoded fields, ie it can contain up to three offsets. The number of offsets results from the flags progressive_sequence, repeat_first_field and top_field_first. <pre id="text">&lt;font style&#61;&quot;vertical&#45;align&#58; inherit&#59;&quot;&gt;&lt;font style&#61;&quot;vertical&#45;align&#58; inherit&#59;&quot;&gt;if ( progressive_sequence &#61;&#61; 1)&lt;/font&gt;&lt;/font&gt;&lt;font&gt;&lt;/font&gt;&lt;font style&#61;&quot;vertical&#45;align&#58; inherit&#59;&quot;&gt;&lt;font style&#61;&quot;vertical&#45;align&#58; inherit&#59;&quot;&gt; &#123; if ( repeat_first_field &#61;&#61; 1 )&lt;/font&gt;&lt;/font&gt;&lt;font&gt;&lt;/font&gt;&lt;font style&#61;&quot;vertical&#45;align&#58; inherit&#59;&quot;&gt;&lt;font style&#61;&quot;vertical&#45;align&#58; inherit&#59;&quot;&gt; &#123; if ( top_field_first &#61;&#61; 1 )&lt;/font&gt;&lt;/font&gt;&lt;font&gt;&lt;/font&gt;&lt;font style&#61;&quot;vertical&#45;align&#58; inherit&#59;&quot;&gt;&lt;font style&#61;&quot;vertical&#45;align&#58; inherit&#59;&quot;&gt; number_of_frame_centre_offsets &#61; 3&lt;/font&gt;&lt;/font&gt;&lt;font&gt;&lt;/font&gt;&lt;font style&#61;&quot;vertical&#45;align&#58; inherit&#59;&quot;&gt;&lt;font style&#61;&quot;vertical&#45;align&#58; inherit&#59;&quot;&gt; else&lt;/font&gt;&lt;/font&gt;&lt;font&gt;&lt;/font&gt;&lt;font style&#61;&quot;vertical&#45;align&#58; inherit&#59;&quot;&gt;&lt;font style&#61;&quot;vertical&#45;align&#58; inherit&#59;&quot;&gt; number_of_frame_centre_offsets &#61; 2&lt;/font&gt;&lt;/font&gt;&lt;font&gt;&lt;/font&gt;&lt;font style&#61;&quot;vertical&#45;align&#58; inherit&#59;&quot;&gt;&lt;font style&#61;&quot;vertical&#45;align&#58; inherit&#59;&quot;&gt; &#125;&lt;/font&gt;&lt;/font&gt;&lt;font&gt;&lt;/font&gt;&lt;font style&#61;&quot;vertical&#45;align&#58; inherit&#59;&quot;&gt;&lt;font style&#61;&quot;vertical&#45;align&#58; inherit&#59;&quot;&gt; else&lt;/font&gt;&lt;/font&gt;&lt;font&gt;&lt;/font&gt;&lt;font style&#61;&quot;vertical&#45;align&#58; inherit&#59;&quot;&gt;&lt;font style&#61;&quot;vertical&#45;align&#58; inherit&#59;&quot;&gt; &#123;&lt;/font&gt;&lt;/font&gt;&lt;font&gt;&lt;/font&gt;&lt;font style&#61;&quot;vertical&#45;align&#58; inherit&#59;&quot;&gt;&lt;font style&#61;&quot;vertical&#45;align&#58; inherit&#59;&quot;&gt; number_of_frame_centre_offsets &#61; 1&lt;/font&gt;&lt;/font&gt;&lt;font&gt;&lt;/font&gt;&lt;font style&#61;&quot;vertical&#45;align&#58; inherit&#59;&quot;&gt;&lt;font style&#61;&quot;vertical&#45;align&#58; inherit&#59;&quot;&gt; &#125;&lt;/font&gt;&lt;/font&gt;&lt;font&gt;&lt;/font&gt;&lt;font style&#61;&quot;vertical&#45;align&#58; inherit&#59;&quot;&gt;&lt;font style&#61;&quot;vertical&#45;align&#58; inherit&#59;&quot;&gt; &#125;&lt;/font&gt;&lt;/font&gt;&lt;font&gt;&lt;/font&gt;&lt;font style&#61;&quot;vertical&#45;align&#58; inherit&#59;&quot;&gt;&lt;font style&#61;&quot;vertical&#45;align&#58; inherit&#59;&quot;&gt; else&lt;/font&gt;&lt;/font&gt;&lt;font&gt;&lt;/font&gt;&lt;font style&#61;&quot;vertical&#45;align&#58; inherit&#59;&quot;&gt;&lt;font style&#61;&quot;vertical&#45;align&#58; inherit&#59;&quot;&gt; &#123; if (picture_structure &#61;&#61; &quot;field&quot;)&lt;/font&gt;&lt;/font&gt;&lt;font&gt;&lt;/font&gt;&lt;font style&#61;&quot;vertical&#45;align&#58; inherit&#59;&quot;&gt;&lt;font style&#61;&quot;vertical&#45;align&#58; inherit&#59;&quot;&gt; &#123; number_of_frame_centre_offsets &#61; 1&lt;/font&gt;&lt;/font&gt;&lt;font&gt;&lt;/font&gt;&lt;font style&#61;&quot;vertical&#45;align&#58; inherit&#59;&quot;&gt;&lt;font style&#61;&quot;vertical&#45;align&#58; inherit&#59;&quot;&gt; &#125;&lt;/font&gt;&lt;/font&gt;&lt;font&gt;&lt;/font&gt;&lt;font style&#61;&quot;vertical&#45;align&#58; inherit&#59;&quot;&gt;&lt;font style&#61;&quot;vertical&#45;align&#58; inherit&#59;&quot;&gt; else&lt;/font&gt;&lt;/font&gt;&lt;font&gt;&lt;/font&gt; &#123; if (repeat_first_field &#61;&#61; 1 )&lt;font&gt;&lt;/font&gt; number_of_frame_centre_offsets &#61; 3&lt;font&gt;&lt;/font&gt; else&lt;font&gt;&lt;/font&gt; number_of_frame_centre_offsets &#61; 2&lt;font&gt;&lt;/font&gt; &#125;&lt;font&gt;&lt;/font&gt; &#125;&lt;font&gt;&lt;/font&gt; </pre> The progressive_sequence flag is included in the sequence extension. repeat_first_field, top_field_first, and picture_structure in the Picture Coding Extension. The absence of the offsets means that the previously used values should be used. That also applies, if not all offsets are given. After a sequence header, null values are used again until values are specified again. </content> </html>

Picture Coding Extension

The extension start code with the ID $B5 is followed by four bits with the extension ID $B8.

Construction

4 bytes: EXTENSION_START_CODE = $000001B5

4 bits: Start Code Identifier - Picture Coding Extension = $8

4 bits: f_code[0][0] - forward horizontal

4 bits: f_code[0][1] - forward vertical

4 bits: f_code[1][0] - backward horizontal

4 bits: f_code[1][1] - backward vertical

2-bit: Intra DC precision

2-bit: Picture Structure

1 bit: top field first

1 bit: Frame Pred Frame DCT

1 bit: Concealment Motion Vectors

1 bit: Q scale type

1 bit: Intra VLC format

1 bit: alternate scan

1 bit: Repeat First Field

1 bit: Chroma 420 type

1 bit: progressive frame

1 bit: Composite Display Flag, if set:

  * 1 bit: V axis
  * 3 bits: field sequence
  * 1 bit: Subcarrier
  * 7 bits: burst amplitude
  * 8 bits: sub-carrier phase

As a scheme:

<html> <content> <table id="byte"> <tbody><tr><td>&nbsp;</td><td>7</td><td>6</td><td>5</td><td>4</td><td>3</td><td>2</td><td>1</td><td>0</td></tr> <tr><td>0</td><td rowspan="4" colspan="8">EXTENSION_START_CODE &nbsp; $000001B5</td></tr> <tr><td>1</td></tr><tr><td>2</td></tr> <tr><td>3</td></tr><tr><td>4</td><td colspan="4">Boot Code Identifier = $8</td><td colspan="4">f_code[0][0]</td></tr> <tr><td>5</td><td colspan="4">f_code[0][1]</td><td colspan="4">f_code[1][0]</td></tr> <tr><td>6</td><td colspan="4">f_code[1][1]</td><td colspan="2">Intra DC Prec.</td><td colspan="2">Picture Structure</td></tr> <tr><td>7</td><td>TFF</td><td>FPF DCT</td><td>CMV</td><td>Q scale type</td><td>Intra VLC format</td><td>Alternate Scan</td><td>Repeat First Field</td><td>Chroma 420 type</td></tr> <tr><td>8th</td><td>Progressive frames</td><td>composite display?</td><td>V axis</td><td colspan="3">Field Sequence</td><td>subcarriers</td><td>burst amplitude</td></tr> <tr><td>9</td><td colspan="6">still BA</td><td colspan="2">sub-carrier phase</td></tr> <tr><td>10</td><td colspan="6">nor SCP</td><td colspan="2">&nbsp;</td></tr> </tbody></table> <h2>Explanations</h2> f_code[s][t] The values &ZeroWidthSpace;&ZeroWidthSpace;are used to decode the motion vectors. The value 0 is forbidden, 1 to 9 and 15 are allowed. Intra DC Precision Accuracy with which the discrete cosine transformation is used. The Intra DC Mult(iplikator) is derived from this. <table id="sheme"> <tbody><tr><th>value</th><th>accuracy</th><th>multiplier</th></tr> <tr><td>00</td><td>8 bits</td><td>8th</td></tr> <tr><td>01</td><td>9 bits</td><td>4</td></tr> <tr><td>10</td><td>10 bits</td><td>2</td></tr> <tr><td>11</td><td>11 bits</td><td>1</td></tr> </tbody></table> Picture Structure <table id="sheme"> <tbody><tr><th>Wert</th><th>Picture Structure</th></tr> <tr><td>00</td><td>Reserviert</td></tr> <tr><td>01</td><td>Top Field - oberes Halbbild</td></tr> <tr><td>10</td><td>Bottom Field - unteres Halbbild</td></tr> <tr><td>11</td><td>Frame Picture - Vollbild</td></tr> </tbody></table> If a frame is encoded in fields, there must always be a pair with the same picture coding type. Top Field First This flag depends on Picture Structure, Progressive Sequence and Repeat First Field. At If the Progressive Sequence flag is not set, it is used during decoding to reconstruct the frame and indicates whether the First Field (upper field) is output first. If the Progressive Sequence flag is set, there is in connection with the Repeat flag First Field indicates how often a frame is output during decoding. This means at Repeat First Field = 0 and Top Field First = 0 becomes a progressive frame, with Repeat First Field = 1 and Top Field First = 0 two identical progressive frames become and with Repeat First Field = 1 and Top Field First = 1, three identical progressive frames are output. Frame Pred Frame DCT If this flag is set, only Frame DCT and Frame Prediction will be used. At Field Picture (fields) it is 0, with progressive frames it is 1. Concealment Motion Vectors This flag indicates whether the intra macroblocks were encoded with motion vectors. Q Scale Type This flag is used for the Quantiser Scale Factor. Intra VLC format This flag is used to determine the DCT coefficients. Alternate Scan This flag is used to determine the DCT coefficients. Repeat First Field If the flags progressisve_sequence (see <a href="projects/mpeg/k010203.htm">Sequence Extension Header</a>) and progressive_frame are not set, the repeat_first_field flag is also not set. When decoding then the frame composed of two fields. If the progressive_sequence flag is not set but the progressive_frame flag is set, the frame is composed of two fields. The first field (top field or bottom field) is specified by the flag top_field_first identified and followed by the other. If the repeat_first_field flag is then set, the frame consists of three fields composed. The first field is determined by the top_field_first flag and is followed by the other. Then will repeats the first field. If the progressive_sequence flag is set and the repeat_first_field flag is not, the frame decoded from a frame. Chroma 420 Type Set the same as Progressive Frame. Exists for historical reasons. Progressive Frame If the flag is not set, it means that the two fields of a frame are two interlaced fields are. Repeat First Field must be 0 (two field duration). If the flag is set, this means that the two fields are combined into one are merged. Picture Structure must be set to "Frame" and Frame Pred Frame DCT to 1. Composite Display Flag This flag is set if the picture from which the MPEG was encoded is (analogue) Composite Video were encoded. The information refers to the extension following picture. Is it a Frame Picture, the information relates to the First Field. The information is adjusted for the second field, as these cannot be saved. The following elements are not used for decoding. The Repeat First Field Flag and the Composite Display Flag must not be set at the same time. V Axis 1-bit integer used only when the bitstream represents a signal that had previously been encoded according to PAL systems. v_axis is set to 1 on a positive sign, v_axis is set to 0 otherwise. Field Sequence Returns the field number of an eight field sequence on a PAL system or a five field sequence for an NTSC system according to the following table: <table id="sheme"> <tbody><tr><th>Field Sequence</th><th>Frame</th><th>Field</th></tr> <tr><td>000</td><td>1</td><td>1</td></tr> <tr><td>001</td><td>1</td><td>2</td></tr> <tr><td>010</td><td>2</td><td>3</td></tr> <tr><td>011</td><td>2</td><td>4</td></tr> <tr><td>100</td><td>3</td><td>5</td></tr> <tr><td>101</td><td>3</td><td>6</td></tr> <tr><td>110</td><td>4</td><td>7</td></tr> <tr><td>111</td><td>4</td><td>8</td></tr> </tbody></table> Sub Carrier If the flag is not set, the sub-carrier/line frequency relationship is correct. Burst Amplitude specifies the burst amplitude for PAL and NTSC. Sub Carrier Phase Indicates the phase of the reference sub carrier of the field synchronization. <table id="sheme"> <tbody><tr><th>Sub Carrier Phase</th><th>Phase</th></tr> <tr><td>0</td><td>([360°] * 0)</td></tr> <tr><td>1</td><td>([360°] * 1)</td></tr> <tr><td>...</td><td>...</td></tr> <tr><td>255</td><td>([360°] * 255)</td></tr> </tbody></table> </content> </html>

Picture Coding Extension

The extension start code with the ID $B5 is followed by four bits with the extension ID $B8.

Construction

4 bytes: EXTENSION_START_CODE = $000001B5

4 bits: Start Code Identifier - Picture Coding Extension = $8

4 bits: f_code[0][0] - forward horizontal

4 bits: f_code[0][1] - forward vertical

4 bits: f_code[1][0] - backward horizontal

4 bits: f_code[1][1] - backward vertical

2-bit: Intra DC precision

2-bit: Picture Structure

1 bit: top field first

1 bit: Frame Pred Frame DCT

1 bit: Concealment Motion Vectors

1 bit: Q scale type

1 bit: Intra VLC format

1 bit: alternate scan

1 bit: Repeat First Field

1 bit: Chroma 420 type

1 bit: progressive frame

1 bit: Composite Display Flag, if set:

  * 1 bit: V axis
  * 3 bits: field sequence
  * 1 bit: Subcarrier
  * 7 bits: burst amplitude
  * 8 bits: sub-carrier phase

  &lt;tbody&gt;&lt;tr&gt;&lt;td&gt;&amp;nbsp;&lt;/td&gt;&lt;td&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;7&lt;/font&gt;&lt;/font&gt;&lt;/td&gt;&lt;td&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;6&lt;/font&gt;&lt;/font&gt;&lt;/td&gt;&lt;td&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;5&lt;/font&gt;&lt;/font&gt;&lt;/td&gt;&lt;td&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;4&lt;/font&gt;&lt;/font&gt;&lt;/td&gt;&lt;td&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;3&lt;/font&gt;&lt;/font&gt;&lt;/td&gt;&lt;td&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;2&lt;/font&gt;&lt;/font&gt;&lt;/td&gt;&lt;td&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;1&lt;/font&gt;&lt;/font&gt;&lt;/td&gt;&lt;td&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;0&lt;/font&gt;&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr&gt;&lt;td&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;0&lt;/font&gt;&lt;/font&gt;&lt;/td&gt;&lt;td rowspan=&quot;4&quot; colspan=&quot;8&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;EXTENSION_START_CODE &lt;/font&gt;&lt;/font&gt;&lt;br /&gt;&amp;nbsp;&lt;br /&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;$000001B5&lt;/font&gt;&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr&gt;&lt;td&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;1&lt;/font&gt;&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;2&lt;/font&gt;&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr&gt;&lt;td&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;3&lt;/font&gt;&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;4&lt;/font&gt;&lt;/font&gt;&lt;/td&gt;&lt;td colspan=&quot;4&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;Boot Code Identifier = $8&lt;/font&gt;&lt;/font&gt;&lt;/td&gt;&lt;td colspan=&quot;4&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;f_code&#91;0&#93;&#91;0&#93;&lt;/font&gt;&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr&gt;&lt;td&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;5&lt;/font&gt;&lt;/font&gt;&lt;/td&gt;&lt;td colspan=&quot;4&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;f_code&#91;0&#93;&#91;1&#93;&lt;/font&gt;&lt;/font&gt;&lt;/td&gt;&lt;td colspan=&quot;4&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;f_code&#91;1&#93;&#91;0&#93;&lt;/font&gt;&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr&gt;&lt;td&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;6&lt;/font&gt;&lt;/font&gt;&lt;/td&gt;&lt;td colspan=&quot;4&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;f_code&#91;1&#93;&#91;1&#93;&lt;/font&gt;&lt;/font&gt;&lt;/td&gt;&lt;td colspan=&quot;2&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;Intra DC Prec.&lt;/font&gt;&lt;/font&gt;&lt;/td&gt;&lt;td colspan=&quot;2&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;Picture Structure&lt;/font&gt;&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr&gt;&lt;td&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;7&lt;/font&gt;&lt;/font&gt;&lt;/td&gt;&lt;td&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;TFF&lt;/font&gt;&lt;/font&gt;&lt;/td&gt;&lt;td&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;FPF &lt;/font&gt;&lt;/font&gt;&lt;br /&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;DCT&lt;/font&gt;&lt;/font&gt;&lt;/td&gt;&lt;td&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;CMV&lt;/font&gt;&lt;/font&gt;&lt;/td&gt;&lt;td&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;Q scale type&lt;/font&gt;&lt;/font&gt;&lt;/td&gt;&lt;td&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;Intra VLC format&lt;/font&gt;&lt;/font&gt;&lt;/td&gt;&lt;td&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;Alternate Scan&lt;/font&gt;&lt;/font&gt;&lt;/td&gt;&lt;td&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;Repeat First Field&lt;/font&gt;&lt;/font&gt;&lt;/td&gt;&lt;td&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;Chroma 420 type&lt;/font&gt;&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr&gt;&lt;td&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;8th&lt;/font&gt;&lt;/font&gt;&lt;/td&gt;&lt;td&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;Progressive frames&lt;/font&gt;&lt;/font&gt;&lt;/td&gt;&lt;td&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;composite display?&lt;/font&gt;&lt;/font&gt;&lt;/td&gt;&lt;td&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;V axis&lt;/font&gt;&lt;/font&gt;&lt;/td&gt;&lt;td colspan=&quot;3&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;Field Sequence&lt;/font&gt;&lt;/font&gt;&lt;/td&gt;&lt;td&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;subcarriers&lt;/font&gt;&lt;/font&gt;&lt;/td&gt;&lt;td&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;burst amplitude&lt;/font&gt;&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr&gt;&lt;td&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;9&lt;/font&gt;&lt;/font&gt;&lt;/td&gt;&lt;td colspan=&quot;6&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;still BA&lt;/font&gt;&lt;/font&gt;&lt;/td&gt;&lt;td colspan=&quot;2&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;sub&#45;carrier phase&lt;/font&gt;&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr&gt;&lt;td&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;10&lt;/font&gt;&lt;/font&gt;&lt;/td&gt;&lt;td colspan=&quot;6&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;nor SCP&lt;/font&gt;&lt;/font&gt;&lt;/td&gt;&lt;td colspan=&quot;2&quot;&gt;&amp;nbsp;&lt;/td&gt;&lt;/tr&gt;

</tbody></table>

<h2>Explanations</h2>

f_code[s][t] The values &ZeroWidthSpace;&ZeroWidthSpace;are used to decode the motion vectors. The value 0 is forbidden, 1 to 9 and 15 are allowed. Intra DC Precision Accuracy with which the discrete cosine transformation is used. The Intra DC Mult(iplikator) is derived from this.

  &lt;tbody&gt;&lt;tr&gt;&lt;th&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;value&lt;/font&gt;&lt;/font&gt;&lt;/th&gt;&lt;th&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;accuracy&lt;/font&gt;&lt;/font&gt;&lt;/th&gt;&lt;th&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;multiplier&lt;/font&gt;&lt;/font&gt;&lt;/th&gt;&lt;/tr&gt;
  &lt;tr&gt;&lt;td&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;00&lt;/font&gt;&lt;/font&gt;&lt;/td&gt;&lt;td&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;8 bits&lt;/font&gt;&lt;/font&gt;&lt;/td&gt;&lt;td&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;8th&lt;/font&gt;&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr&gt;&lt;td&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;01&lt;/font&gt;&lt;/font&gt;&lt;/td&gt;&lt;td&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;9 bits&lt;/font&gt;&lt;/font&gt;&lt;/td&gt;&lt;td&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;4&lt;/font&gt;&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr&gt;&lt;td&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;10&lt;/font&gt;&lt;/font&gt;&lt;/td&gt;&lt;td&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;10 bits&lt;/font&gt;&lt;/font&gt;&lt;/td&gt;&lt;td&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;2&lt;/font&gt;&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr&gt;&lt;td&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;11&lt;/font&gt;&lt;/font&gt;&lt;/td&gt;&lt;td&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;11 bits&lt;/font&gt;&lt;/font&gt;&lt;/td&gt;&lt;td&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;&lt;font style=&quot;vertical&#45;align: inherit;&quot;&gt;1&lt;/font&gt;&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;

</tbody></table>

Picture Structure <table id="sheme">

  &lt;tbody&gt;&lt;tr&gt;&lt;th&gt;Wert&lt;/th&gt;&lt;th&gt;Picture Structure&lt;/th&gt;&lt;/tr&gt;
  &lt;tr&gt;&lt;td&gt;00&lt;/td&gt;&lt;td&gt;Reserviert&lt;/td&gt;&lt;/tr&gt;
  &lt;tr&gt;&lt;td&gt;01&lt;/td&gt;&lt;td&gt;Top Field &#45; upper Field&lt;/td&gt;&lt;/tr&gt;
  &lt;tr&gt;&lt;td&gt;10&lt;/td&gt;&lt;td&gt;Bottom Field &#45; lower Field&lt;/td&gt;&lt;/tr&gt;
  &lt;tr&gt;&lt;td&gt;11&lt;/td&gt;&lt;td&gt;Frame Picture &#45; progressive&lt;/td&gt;&lt;/tr&gt;

</tbody></table>

If a frame is encoded in fields, there must always be a pair with the same picture coding type. Top Field First This flag depends on Picture Structure, Progressive Sequence and Repeat First Field. At

Frame Pred Frame DCT If this flag is set, only Frame DCT and Frame Prediction will be used. At Field Picture

   (fields) it is 0, with progressive frames it is 1.&lt;/p&gt;

Concealment Motion Vectors This flag indicates whether the intra macroblocks were encoded with motion vectors. Q Scale Type This flag is used for the Quantiser Scale Factor. Intra VLC format This flag is used to determine the DCT coefficients. Alternate Scan This flag is used to determine the DCT coefficients. Repeat First Field

If the flags progressisve_sequence (see <a href="projects/mpeg/k010203.htm">Sequence Extension

Chroma 420 Type Set the same as Progressive Frame. Exists for historical reasons. Progressive Frame If the flag is not set, it means that the two fields of a frame are two interlaced fields

   are. Repeat First Field must be 0 (two field duration). If the flag is set, this means that the two fields are combined into one
   are merged. Picture Structure must be set to &quot;Frame&quot; and Frame Pred Frame DCT to 1.&lt;/p&gt;

Composite Display Flag This flag is set if the picture from which the MPEG was encoded is (analogue)

V Axis 1-bit integer used only when the bitstream represents a signal that had previously been encoded according to

   PAL systems. v_axis is set to 1 on a positive sign, v_axis is set to 0 otherwise.&lt;/p&gt;

Field Sequence Returns the field number of an eight field sequence on a PAL system or a five field sequence

  &lt;tbody&gt;&lt;tr&gt;&lt;th&gt;Field Sequence&lt;/th&gt;&lt;th&gt;Frame&lt;/th&gt;&lt;th&gt;Field&lt;/th&gt;&lt;/tr&gt;
  &lt;tr&gt;&lt;td&gt;000&lt;/td&gt;&lt;td&gt;1&lt;/td&gt;&lt;td&gt;1&lt;/td&gt;&lt;/tr&gt;
  &lt;tr&gt;&lt;td&gt;001&lt;/td&gt;&lt;td&gt;1&lt;/td&gt;&lt;td&gt;2&lt;/td&gt;&lt;/tr&gt;
  &lt;tr&gt;&lt;td&gt;010&lt;/td&gt;&lt;td&gt;2&lt;/td&gt;&lt;td&gt;3&lt;/td&gt;&lt;/tr&gt;
  &lt;tr&gt;&lt;td&gt;011&lt;/td&gt;&lt;td&gt;2&lt;/td&gt;&lt;td&gt;4&lt;/td&gt;&lt;/tr&gt;
  &lt;tr&gt;&lt;td&gt;100&lt;/td&gt;&lt;td&gt;3&lt;/td&gt;&lt;td&gt;5&lt;/td&gt;&lt;/tr&gt;
  &lt;tr&gt;&lt;td&gt;101&lt;/td&gt;&lt;td&gt;3&lt;/td&gt;&lt;td&gt;6&lt;/td&gt;&lt;/tr&gt;
  &lt;tr&gt;&lt;td&gt;110&lt;/td&gt;&lt;td&gt;4&lt;/td&gt;&lt;td&gt;7&lt;/td&gt;&lt;/tr&gt;
  &lt;tr&gt;&lt;td&gt;111&lt;/td&gt;&lt;td&gt;4&lt;/td&gt;&lt;td&gt;8&lt;/td&gt;&lt;/tr&gt;

</tbody></table>

Sub Carrier If the flag is not set, the sub-carrier/line frequency relationship is correct. Burst Amplitude specifies the burst amplitude for PAL and NTSC. Sub Carrier Phase Indicates the phase of the reference sub carrier of the field synchronization. <table id="sheme">

  &lt;tbody&gt;&lt;tr&gt;&lt;th&gt;Sub Carrier Phase&lt;/th&gt;&lt;th&gt;Phase&lt;/th&gt;&lt;/tr&gt;
  &lt;tr&gt;&lt;td&gt;0&lt;/td&gt;&lt;td&gt;(&#91;360°&#93; * 0)&lt;/td&gt;&lt;/tr&gt;
  &lt;tr&gt;&lt;td&gt;1&lt;/td&gt;&lt;td&gt;(&#91;360°&#93; * 1)&lt;/td&gt;&lt;/tr&gt;
  &lt;tr&gt;&lt;td&gt;...&lt;/td&gt;&lt;td&gt;...&lt;/td&gt;&lt;/tr&gt;
  &lt;tr&gt;&lt;td&gt;255&lt;/td&gt;&lt;td&gt;(&#91;360°&#93; * 255)&lt;/td&gt;&lt;/tr&gt;

</tbody></table>

</html></content>

Macroblock

A macroblock has a size of 16 * 16 pixels. It consists of 4 blocks of 8 * 8 pixels with gray values (Y). These are supplemented by two blocks of 8 * 8 pixels with chrominance values. Chrominance values mean color values. One block for Red (Cr) and one for Blue (Cb).

  * Addr Incr: number of MBs to skip.
  * Type: Does this MB use a motion vector? What type?
  * QScale: How is the quantization table scaled in this MB?
  * Coded Block Pattern (CBP): bitmap indicating which blocks are coded.

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Table of Contents

MPEG-2 Elementary Video

Structure of an MPEG-2 program stream.

Sequence headers

Construction

extensions

Sequence Extension

Construction

Sequence Display Extension

Construction

Quant Matrix Extension

Construction

Copyright extension

Construction

Sequence Scalable Extension

Construction

Group of Pictures

Construction

Picture Display Extension

Construction

Picture Coding Extension

Construction

Picture Coding Extension

Construction

Macroblock

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