feat: refactor folder structure & add new codec parser and gen & add unit tests

packages/matroska/src/codecs/avc.ts

@@ -0,0 +1,148 @@
+import { ParseCodecError } from '@konoplayer/core/errors';
+import { type } from 'arktype';
+import type { TrackEntryType } from '../schema';
+
+export const AVC_CODEC_TYPE = 'h264(AVC)';
+
+export const AVCDecoderConfigurationRecordSchema = type({
+  configurationVersion: type.number, // Configuration version, typically 1
+  avcProfileIndication: type.number, // AVC profile
+  profileCompatibility: type.number, // Profile compatibility
+  avcLevelIndication: type.number, // AVC level
+  lengthSizeMinusOne: type.number, // NAL unit length field size minus 1
+  sps: type
+    .instanceOf(Uint8Array<ArrayBufferLike>)
+    .array()
+    .atLeastLength(1), // Sequence Parameter Sets (SPS)
+  pps: type
+    .instanceOf(Uint8Array<ArrayBufferLike>)
+    .array()
+    .atLeastLength(1), // Picture Parameter Sets (PPS)
+});
+
+export type AVCDecoderConfigurationRecordType =
+  typeof AVCDecoderConfigurationRecordSchema.infer;
+
+/**
+ *
+ * @see [webkit](https://github.com/movableink/webkit/blob/7e43fe7000b319ce68334c09eed1031642099726/Source/WebCore/platform/graphics/HEVCUtilities.cpp#L84)
+ */
+export function parseAVCDecoderConfigurationRecord(
+  track: TrackEntryType
+): AVCDecoderConfigurationRecordType {
+  // ISO/IEC 14496-10:2014
+  // 7.3.2.1.1 Sequence parameter set data syntax
+  const codecPrivate = track.CodecPrivate;
+
+  if (!codecPrivate) {
+    throw new ParseCodecError(
+      AVC_CODEC_TYPE,
+      'CodecPrivate of AVC Track is missing'
+    );
+  }
+
+  // AVCDecoderConfigurationRecord is at a minimum 24 bytes long
+  if (codecPrivate.length < 24) {
+    throw new ParseCodecError(
+      AVC_CODEC_TYPE,
+      'Input data too short for AVCDecoderConfigurationRecord'
+    );
+  }
+
+  const view = new DataView(codecPrivate.buffer);
+  let offset = 0;
+
+  const readUint8 = (move: boolean) => {
+    const result = view.getUint8(offset);
+    if (move) {
+      offset += 1;
+    }
+    return result;
+  };
+
+  const readUint16 = (move: boolean) => {
+    const result = view.getUint16(offset, false);
+    if (move) {
+      offset += 2;
+    }
+    return result;
+  };
+
+  const configurationVersion = readUint8(true);
+  const avcProfileIndication = readUint8(true);
+  const profileCompatibility = readUint8(true);
+  const avcLevelIndication = readUint8(true);
+
+  // Read lengthSizeMinusOne (first 6 bits are reserved, typically 0xFF, last 2 bits are the value)
+  const lengthSizeMinusOne = readUint8(true) & 0x03;
+
+  // Read number of SPS (first 3 bits are reserved, typically 0xE0, last 5 bits are SPS count)
+  const numOfSPS = readUint8(true) & 0x1f;
+  const sps: Uint8Array[] = [];
+
+  // Parse SPS
+  for (let i = 0; i < numOfSPS; i++) {
+    if (offset + 2 > codecPrivate.length) {
+      throw new ParseCodecError(AVC_CODEC_TYPE, 'Invalid SPS length');
+    }
+
+    const spsLength = readUint16(true);
+
+    if (offset + spsLength > codecPrivate.length) {
+      throw new ParseCodecError(
+        AVC_CODEC_TYPE,
+        'SPS data exceeds buffer length'
+      );
+    }
+
+    sps.push(codecPrivate.subarray(offset, offset + spsLength));
+    offset += spsLength;
+  }
+
+  // Read number of PPS
+  if (offset >= codecPrivate.length) {
+    throw new ParseCodecError(AVC_CODEC_TYPE, 'No space for PPS count');
+  }
+  const numOfPPS = readUint8(true);
+  const pps: Uint8Array[] = [];
+
+  // Parse PPS
+  for (let i = 0; i < numOfPPS; i++) {
+    if (offset + 2 > codecPrivate.length) {
+      throw new ParseCodecError(AVC_CODEC_TYPE, 'Invalid PPS length');
+    }
+
+    const ppsLength = readUint16(true);
+
+    if (offset + ppsLength > codecPrivate.length) {
+      throw new ParseCodecError(
+        AVC_CODEC_TYPE,
+        'PPS data exceeds buffer length'
+      );
+    }
+
+    pps.push(codecPrivate.subarray(offset, offset + ppsLength));
+    offset += ppsLength;
+  }
+
+  return {
+    configurationVersion,
+    avcProfileIndication,
+    profileCompatibility,
+    avcLevelIndication,
+    lengthSizeMinusOne,
+    sps,
+    pps,
+  };
+}
+
+export function genCodecStringByAVCDecoderConfigurationRecord(
+  config: AVCDecoderConfigurationRecordType
+): string {
+  const profileHex = config.avcProfileIndication.toString(16).padStart(2, '0');
+  const profileCompatHex = config.profileCompatibility
+    .toString(16)
+    .padStart(2, '0');
+  const levelHex = config.avcLevelIndication.toString(16).padStart(2, '0');
+  return `avc1.${profileHex}${profileCompatHex}${levelHex}`;
+}