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media-codecs

v3.0.0

Published

Get a codec parameter string (like 'avc1.4d002a') from human readable options (like { name: 'Main', level: '4.2' }) and back to a descriptive name ('AVC Main Profile Level 4.2').

Readme

media-codecs

npm version stability-stable npm minzipped size dependencies types Conventional Commits styled with prettier linted with eslint license

Get a codec parameter string (like "avc1.4d002a") from human readable options (like { name: "Main", level: "4.2" }) and back to a descriptive name ("AVC Main Profile Level 4.2").

Useful for checking supported codecs with HTMLMediaElement.canPlayType / MediaSource.isTypeSupported and to pass as option for the WebCodecs API VideoEncoder configure parameters. Supports Advanced Video Coding (AVC), Video Partition (VP8/VP9), AOMedia Video (AV1) and partially High Efficiency Video Coding HEVC.

See the demo that checks current browser support of all video codecs and MDN's Codecs in common media types.

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Installation

npm install media-codecs

Usage

import { AVC } from "media-codecs";

const codec = AVC.getCodec({ profile: "Main", level: "4.2" });
// => avc1.4d002a
const mimeType = `video/mp4;codecs="${codec}"`;

console.log(MediaSource.isTypeSupported(mimeType));

Roadmap:

  • [ ] HEVC compatibility and constraints
  • [ ] VP, HEVC and AV1 optional parameters

API

Modules

Typedefs

media-codecs

media-codecs.VP : vp

Kind: static property of media-codecs

media-codecs.AV : av

Kind: static property of media-codecs

media-codecs.AVC : avc

Kind: static property of media-codecs

media-codecs.HEVC : hevc

Kind: static property of media-codecs

av

av.AV_CODECS : Array.<CodecItem>

List of codecs

Kind: static constant of av

av.AV_PROFILES : Array.<AVProfileItem>

List of AV profiles numbers

Kind: static constant of av See: av1-spec

av.AV_LEVELS : Array.<string>

AV Levels

Kind: static constant of av See: av1-spec

av.AV_TIER : Array.<string>

List of supported tier

Kind: static constant of av

av.AV_BIT_DEPTH : Array.<number>

List of supported bit depth

Kind: static constant of av

av.getAllItems() ⇒ Array.<MediaCodecItem>

Return a list of all possible codec parameter string and their human readable names

Kind: static method of av

av.getCodec(options) ⇒ string

Get a codec parameter string

Kind: static method of av

| Param | Type | | ------- | ---------------------------------------------- | | options | AVCodecOptions |

av.getCodecName(codec) ⇒ string

Get a codec human readbable name

Kind: static method of av

| Param | Type | Description | | ----- | ------------------- | -------------------------------------------------- | | codec | string | a codec string (av01.P.LLT.DD eg. "av01.P.LLT.DD") |

avc

avc.AVC_PROFILES : Array.<AVCProfileItem>

List of profiles with their profile numbers (PP) and the constraints component (CC).

Kind: static constant of avc

avc.AVC_LEVELS : Array.<number>

AVC Levels

Kind: static constant of avc See: wikipedia.org

avc.getAllItems() ⇒ Array.<MediaCodecItem>

Return a list of all possible codec parameter string and their human readable names

Kind: static method of avc

avc.getCodec(options) ⇒ string

Get a codec parameter string

Kind: static method of avc

| Param | Type | | ------- | ------------------------------------------------ | | options | AVCCodecOptions |

avc.getCodecName(codec) ⇒ string

Get a codec human readbable name

Kind: static method of avc

| Param | Type | Description | | ----- | ------------------- | -------------------------------------------------- | | codec | string | a codec string (cccc.PP.LL.DD eg. "vp09.00.10.08") |

hevc

hevc.HEVC_PROFILES : Array.<HEVCProfileItem>

List of profiles with their profile numbers (PP), profile compatibility flags (C), and default constraint bytes.

C is a hex string where bit N being set means the stream conforms to HEVC profile N. constraints holds up to 6 bytes encoding general source and profile-specific constraint flags; trailing zero bytes are omitted when formatted.

Kind: static constant of hevc See: hevc-spec

hevc.HEVC_CONSTRAINTS : Array.<Array.<string>>

Constraint arrays for standard profiles (PP 1, 2, 3).

Only byte 0 is used; its layout is: bit 7: general_progressive_source_flag bit 6: general_interlaced_source_flag bit 5: general_non_packed_constraint_flag bit 4: general_frame_only_constraint_flag bit 3: general_one_picture_only_constraint_flag bits 2–0: reserved zero 32 entries covering all combinations of bits 7–3.

Kind: static constant of hevc

hevc.HEVC_REXT_CONSTRAINTS : Array.<Array.<string>>

Constraint arrays for RExt non-HT profiles (PP 4, 6, 7, 8).

Byte 0: bits 7–4: source flags (progressive, interlaced, non_packed, frame_only) bit 3: general_max_12bit_constraint_flag bit 2: general_max_10bit_constraint_flag (implies max_12bit) bit 1: general_max_8bit_constraint_flag (implies max_10bit) bit 0: general_max_422chroma_constraint_flag

Byte 1 (omitted when all zero): bit 7: general_max_420chroma_constraint_flag (implies max_422chroma) bit 6: general_max_monochrome_constraint_flag (implies max_420chroma) bit 5: general_intra_constraint_flag bit 4: general_one_picture_only_constraint_flag bit 3: general_lower_bit_rate_constraint_flag bits 2–0: reserved zero

Monotonic depth: max_8bit → max_10bit → max_12bit (4 valid combos). Monotonic chroma: max_monochrome → max_420chroma → max_422chroma (4 valid combos). 2048 entries total (16 source × 4 depth × 4 chroma × 2 intra × 2 opo × 2 lbr).

Kind: static constant of hevc

hevc.HEVC_HT_CONSTRAINTS : Array.<Array.<string>>

Constraint arrays for HT profiles (PP 5, 9, 10, 11).

Same byte layout as HEVC_REXT_CONSTRAINTS but byte 1 bit 2 carries general_max_14bit_constraint_flag, extending the depth hierarchy: max_8bit → max_10bit → max_12bit → max_14bit (5 valid depth combos). 2560 entries total (16 source × 5 depth × 4 chroma × 2 intra × 2 opo × 2 lbr).

Kind: static constant of hevc

hevc.HEVC_LEVELS : Array.<string>

HEVC Levels

Kind: static constant of hevc See: hevc-levels

hevc.HEVC_TIER : Array.<string>

List of supported tier

Kind: static constant of hevc

hevc.formatConstraints(constraints) ⇒ string

Format up to 6 constraint bytes as a dot-separated lowercase hex string, omitting trailing zero bytes.

Kind: static method of hevc

| Param | Type | | ----------- | --------------------------------- | | constraints | Array.<string> |

hevc.getAllItems([defaultConstraints]) ⇒ Array.<MediaCodecItem>

Return a list of all possible codec parameter string and their human readable names

Kind: static method of hevc

| Param | Type | Default | Description | | -------------------- | -------------------- | ------------------ | --------------------------------------------------------------------- | | [defaultConstraints] | boolean | false | when true, return only items using each profile's default constraints |

hevc.getCodec(options) ⇒ string

Get a codec parameter string

Kind: static method of hevc

| Param | Type | | ------- | -------------------------------------------------- | | options | HEVCCodecOptions |

hevc.getCodecName(codec) ⇒ string

Get a codec human readable name

Kind: static method of hevc

| Param | Type | Description | | ----- | ------------------- | -------------------------------------- | | codec | string | a codec string (eg. "hev1.1.6.L93.b0") |

vp

vp.VP_CODECS : Array.<CodecItem>

List of codecs

Kind: static constant of vp

vp.VP_PROFILES : Array.<number>

List of VP profiles numbers

Kind: static constant of vp

vp.VP_LEVELS : Array.<string>

VP Levels

Kind: static constant of vp See: webmproject.org

vp.VP_BIT_DEPTH : Array.<number>

List of supported bit depth

Kind: static constant of vp

vp.getAllItems() ⇒ Array.<MediaCodecItem>

Return a list of all possible codec parameter string and their human readable names

Kind: static method of vp

vp.getCodec(options) ⇒ string

Get a codec parameter string

Kind: static method of vp

| Param | Type | | ------- | ---------------------------------------------- | | options | VPCodecOptions |

vp.getCodecName(codec) ⇒ string

Get a codec human readbable name

Kind: static method of vp

| Param | Type | Description | | ----- | ------------------- | ------------------------------------------------ | | codec | string | a codec string (avc1[.PPCCLL] eg. "avc1.640028") |

AVProfileItem : object

Kind: global typedef Properties

| Name | Type | Description | | ---- | ------------------- | ----------------------------- | | name | string | | | P | string | profile numbers (seq_profile) |

AVCProfileItem : object

Kind: global typedef Properties

| Name | Type | Description | | ---- | ------------------- | ----------------------------------- | | name | string | | | PP | string | profile numbers as hex string | | CC | string | constraints component as hex string |

HEVCProfileItem : object

Kind: global typedef Properties

| Name | Type | Description | | ----------- | --------------------------------- | ------------------------------------------------------------------------------------------------- | | name | string | | | PP | string | profile numbers as decimal string | | C | string | profile compatibility flags as hex string (bit N set = conforms to HEVC profile N) | | constraints | Array.<string> | default constraint bytes as hex strings (up to 6); trailing "00" bytes are omitted when formatted |

CodecItem : object

Kind: global typedef Properties

| Name | Type | Description | | ---- | ------------------- | ----------------------------------- | | name | string | | | cccc | string | the four-character ID for the codec |

MediaCodecItem : object

Kind: global typedef Properties

| Name | Type | | ----- | ------------------- | | name | string | | codec | string |

VPCodecOptions : object

Kind: global typedef Properties

| Name | Type | Description | | -------- | ------------------- | ----------------------------------------- | | name | string | Human readable codec name: "VP8" or "VP9" | | profile | number | 0, 1, 2 or 3 | | level | string | | | bitDepth | number | |

AVCodecOptions : object

Kind: global typedef Properties

| Name | Type | Description | | -------- | ------------------- | --------------------------------------------------------------- | | name | string | Human readable codec name: "AV1", potentially AV2 in the future | | profile | string | AV profile name: "Main", "High" or "Professional" | | level | string | | | tier | string | "Main" or "High" | | bitDepth | number | 8, 10 or 12 |

AVCCodecOptions : object

Kind: global typedef Properties

| Name | Type | Description | | ------- | ------------------- | --------------------------------- | | profile | string | AVC profile name (eg. "Baseline") | | level | string | |

HEVCCodecOptions : object

Kind: global typedef Properties

| Name | Type | Description | | ------------- | --------------------------------- | --------------------------------------------------------------------------------------- | | profile | string | HEVC profile name (eg. "Main 10") | | level | string | | | tier | string | "Main" or "High" | | [constraints] | Array.<string> | up to 6 constraint bytes as hex strings; defaults to the profile's standard constraints |

License

MIT. See license file.