@tianfeng98/hls.js/src/remux/hevc-helper.ts

HLS.js is a JavaScript library that supports playing MPEG-TS and HEVC encoded HLS streams in browsers with support for MSE.

export type HEVCDecoderConfigurationRecordType = {
  configurationVersion: 1;
} & VPSHEVCDecoderConfigurationRecordType &
  SPSHEVCDecoderConfigurationRecordType &
  PPSHEVCDecoderConfigurationRecordType;

export type VPSHEVCDecoderConfigurationRecordType = {
  num_temporal_layers: number;
  temporal_id_nested: boolean;
};

export type SPSHEVCDecoderConfigurationRecordType = {
  general_profile_space: number;
  general_tier_flag: number;
  general_level_idc: number;
  general_profile_idc: number;
  general_profile_compatibility_flags_1: number;
  general_profile_compatibility_flags_2: number;
  general_profile_compatibility_flags_3: number;
  general_profile_compatibility_flags_4: number;
  general_constraint_indicator_flags_1: number;
  general_constraint_indicator_flags_2: number;
  general_constraint_indicator_flags_3: number;
  general_constraint_indicator_flags_4: number;
  general_constraint_indicator_flags_5: number;
  general_constraint_indicator_flags_6: number;
  constant_frame_rate: number;
  min_spatial_segmentation_idc: number;
  chroma_format_idc: number;
  bit_depth_luma_minus8: number;
  bit_depth_chroma_minus8: number;
};

export type PPSHEVCDecoderConfigurationRecordType = {
  parallelismType: number;
};
export class HEVCDecoderConfigurationRecord {
  private data: Uint8Array;

  // sps, pps: require Nalu without 4 byte length-header
  public constructor(
    vps: Uint8Array,
    sps: Uint8Array,
    pps: Uint8Array,
    detail: HEVCDecoderConfigurationRecordType,
  ) {
    const length =
      23 +
      (3 + 2 + vps.byteLength) +
      (3 + 2 + sps.byteLength) +
      (3 + 2 + pps.byteLength);
    const data = (this.data = new Uint8Array(length));

    data[0] = 0x01; // configurationVersion
    data[1] =
      ((detail.general_profile_space & 0x03) << 6) |
      ((detail.general_tier_flag ? 1 : 0) << 5) |
      (detail.general_profile_idc & 0x1f);
    data[2] = detail.general_profile_compatibility_flags_1;
    data[3] = detail.general_profile_compatibility_flags_2;
    data[4] = detail.general_profile_compatibility_flags_3;
    data[5] = detail.general_profile_compatibility_flags_4;
    data[6] = detail.general_constraint_indicator_flags_1;
    data[7] = detail.general_constraint_indicator_flags_2;
    data[8] = detail.general_constraint_indicator_flags_3;
    data[9] = detail.general_constraint_indicator_flags_4;
    data[10] = detail.general_constraint_indicator_flags_5;
    data[11] = detail.general_constraint_indicator_flags_6;
    data[12] = detail.general_level_idc;
    data[13] = 0xf0 | ((detail.min_spatial_segmentation_idc & 0x0f00) >> 8);
    data[14] = detail.min_spatial_segmentation_idc & 0xff;
    data[15] = 0xfc | (detail.parallelismType & 0x03);
    data[16] = 0xfc | (detail.chroma_format_idc & 0x03);
    data[17] = 0xf8 | (detail.bit_depth_luma_minus8 & 0x07);
    data[18] = 0xf8 | (detail.bit_depth_chroma_minus8 & 0x07);
    data[19] = 0;
    data[20] = 0;
    data[21] =
      ((detail.constant_frame_rate & 0x03) << 6) |
      ((detail.num_temporal_layers & 0x07) << 3) |
      ((detail.temporal_id_nested ? 1 : 0) << 2) |
      3;
    data[22] = 3;
    data[23 + 0 + 0] = 0x80 | 32;
    data[23 + 0 + 1] = 0;
    data[23 + 0 + 2] = 1;
    data[23 + 0 + 3] = (vps.byteLength & 0xff00) >> 8;
    data[23 + 0 + 4] = (vps.byteLength & 0x00ff) >> 0;
    data.set(vps, 23 + 0 + 5);
    data[23 + (5 + vps.byteLength) + 0] = 0x80 | 33;
    data[23 + (5 + vps.byteLength) + 1] = 0;
    data[23 + (5 + vps.byteLength) + 2] = 1;
    data[23 + (5 + vps.byteLength) + 3] = (sps.byteLength & 0xff00) >> 8;
    data[23 + (5 + vps.byteLength) + 4] = (sps.byteLength & 0x00ff) >> 0;
    data.set(sps, 23 + (5 + vps.byteLength) + 5);
    data[23 + (5 + vps.byteLength + 5 + sps.byteLength) + 0] = 0x80 | 34;
    data[23 + (5 + vps.byteLength + 5 + sps.byteLength) + 1] = 0;
    data[23 + (5 + vps.byteLength + 5 + sps.byteLength) + 2] = 1;
    data[23 + (5 + vps.byteLength + 5 + sps.byteLength) + 3] =
      (pps.byteLength & 0xff00) >> 8;
    data[23 + (5 + vps.byteLength + 5 + sps.byteLength) + 4] =
      (pps.byteLength & 0x00ff) >> 0;
    data.set(pps, 23 + (5 + vps.byteLength + 5 + sps.byteLength) + 5);
  }

  public getData() {
    return this.data;
  }
}