@isomp4/box-moof/dist/tfhd.js

Implements encoding and decoding of the moof box type

import { FullBoxEncoding, readSafeUInt64BE } from "@isomp4/core";
export var TrackFragmentHeaderBox;
(function (TrackFragmentHeaderBox) {
    function parseFlags(flags) {
        return {
            baseDataOffsetPresent: (flags & 0x000001) !== 0,
            sampleDescriptionIndexPresent: (flags & 0x000002) !== 0,
            defaultSampleDurationPresent: (flags & 0x000008) !== 0,
            defaultSampleSizePresent: (flags & 0x000010) !== 0,
            defaultSampleFlagsPresent: (flags & 0x000020) !== 0,
            durationIsEmpty: (flags & 0x010000) !== 0,
            defaultBaseIsMoof: (flags & 0x020000) !== 0,
        };
    }
    TrackFragmentHeaderBox.parseFlags = parseFlags;
})(TrackFragmentHeaderBox || (TrackFragmentHeaderBox = {}));
class TrackFragmentHeaderBoxEncoding extends FullBoxEncoding {
    constructor() {
        super("tfhd");
    }
    encodingLength(obj) {
        return super.encodingLength(obj); // TODO implement
    }
    encodeTo(obj, buffer) {
        const requiredBytes = super.encodeTo(obj, buffer);
        if (requiredBytes > 0) {
            return requiredBytes;
        }
        // let offset = this.encodedBytes;
        // // TODO implementing encoding
        // this.encodedBytes = offset;
        return 0;
    }
    decode(buffer, header) {
        const superBox = super.decode(buffer, header);
        if (typeof superBox === "number") {
            return superBox;
        }
        let offset = this.decodedBytes;
        if (buffer.length < offset + 4) {
            return offset + 4;
        }
        const trackID = buffer.readUInt32BE(offset);
        offset += 4;
        const flags = TrackFragmentHeaderBox.parseFlags(superBox.flags);
        let baseDataOffset;
        if (flags.baseDataOffsetPresent) {
            if (buffer.length < offset + 8) {
                return offset + 8;
            }
            baseDataOffset = readSafeUInt64BE(buffer, offset);
            offset += 8;
        }
        let sampleDescriptionIndex;
        if (flags.sampleDescriptionIndexPresent) {
            if (buffer.length < offset + 4) {
                return offset + 4;
            }
            sampleDescriptionIndex = buffer.readUInt32BE(offset);
            offset += 4;
        }
        let defaultSampleDuration;
        if (flags.defaultSampleDurationPresent) {
            if (buffer.length < offset + 4) {
                return offset + 4;
            }
            defaultSampleDuration = buffer.readUInt32BE(offset);
            offset += 4;
        }
        let defaultSampleSize;
        if (flags.defaultSampleSizePresent) {
            if (buffer.length < offset + 4) {
                return offset + 4;
            }
            defaultSampleSize = buffer.readUInt32BE(offset);
            offset += 4;
        }
        let defaultSampleFlags;
        if (flags.defaultSampleFlagsPresent) {
            if (buffer.length < offset + 4) {
                return offset + 4;
            }
            defaultSampleFlags = buffer.readUInt32BE(offset);
            offset += 4;
        }
        this.decodedBytes = offset;
        return {
            ...superBox,
            trackID,
            baseDataOffset,
            sampleDescriptionIndex,
            defaultSampleDuration,
            defaultSampleSize,
            defaultSampleFlags,
        };
    }
}
export const tfhd = new TrackFragmentHeaderBoxEncoding();