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[WIP] Metadata #104

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[WIP] Metadata #104

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Original file line number Diff line number Diff line change
Expand Up @@ -1038,6 +1038,13 @@ Parameters( ) { |
ec | ur
intra | ur
} |
if (version == 3 && micro_version >= 5) { |{V3}
if ((version == 3 && micro_version >= 5) |{V4}
|| version >= 4) { |{V4}
width | ur
height | ur
Metadata( ) |
} |
} |
```

Expand Down Expand Up @@ -1070,6 +1077,7 @@ Meaning of micro_version for version 3:
|-------|:------------------------|
|0...3 | reserved\* |
|4 | first stable variant |
|5 | frame size and metadata |
|Other | reserved for future use |

\* development versions which may be incompatible with the stable variants.
Expand Down Expand Up @@ -1215,6 +1223,14 @@ Inferred to be 0 if not present.
|1 | Frames are independent (keyframes only) |
|Other | reserved for future use |

### width

0 if unspecified in the bitstream (provided by container)

### height

0 if unspecified in the bitstream (provided by container)

## Quantization Table Set

The Quantization Table Sets are stored by storing the number of equal entries -1 of the first half of the table (represented as `len - 1` in the pseudo-code below) using the method described in [Range Non Binary Values](#range-non-binary-values). The second half doesn’t need to be stored as it is identical to the first with flipped sign. `scale` and `len_count[ i ][ j ]` are temporary values used for the computing of `context_count[ i ]` and are not used outside Quantization Table Set pseudo-code.
Expand Down Expand Up @@ -1271,6 +1287,54 @@ QuantizationTable(i, j, scale) { |

`context_count[ i ]` indicates the count of contexts for Quantization Table Set `i`.

## Metadata

(Intro TODO). A tool using a bitstream conforming to this specification SHOULD prioritize metadata in the bitstream over metadata in the container.

```c
pseudo-code | type
--------------------------------------------------------------|-----
Metadata( ) { |
metadata_count | ur
for( i = 0; i < metadata_count; i++ ) { |
metadata_id | ur
metadata_type | ur
metadata_size [ i ] - 1 | ur
for( j = 0; j < metadata_size [ i ]; j++ ) { |
if (metadata_type == 0) |
metadata_content [ i ] [ j ] | br
if (metadata_type == 1) |
metadata_content [ i ] [ j ] | ur
if (metadata_type == 2) |
metadata_content [ i ] [ j ] | sr
} |
} |
} |
```

### metadata_count

### metadata_id

|value | metadata meaning |
|-------|:-----------------------------------------------------------------|
|0 | Range (1 = Broadcast, 2 = Full...) |
|1 | Primaries |
|2 | TransferCharacteristics |
|3 | MatrixCoefficients |
|4 | MaxCLL |
|5 | MaxFALL |
|6 | PrimaryRChromaticityX |
|... | (TODO) |
| | WhitePointChromaticityY |
| | ChromaSitingHorz |
| | Encoding library name and version (e.g. "Lavc57.107.100 ffv1") |
|Other | reserved for future use |

### metadata_type

### metadata_content

# Restrictions

To ensure that fast multithreaded decoding is possible, starting version 3 and if frame\_pixel\_width * frame\_pixel\_height is more than 101376, slice\_width * slice\_height MUST be less or equal to num\_h\_slices * num\_v\_slices / 4.
Expand Down