SoundFontSampleData.fromReader constructor

SoundFontSampleData.fromReader(BinaryReader reader)

Implementation

factory SoundFontSampleData.fromReader(BinaryReader reader)
{
    String chunkId = reader.readFourCC();

    if (chunkId != "LIST")
    {
        throw "The LIST chunk was not found.";
    }

    int end = reader.readInt32();
    end += reader.pos;

    String listType = reader.readFourCC();

    if (listType != "sdta")
    {
        throw "The type of the LIST chunk must be 'sdta', but was '$listType'.";
    }

    int? bitsPerSample;
    ArrayInt16? samples;

    while (reader.pos < end)
    {
        String id = reader.readFourCC();
        int size = reader.readInt32();

        switch (id)
        {
            case "smpl":

                if (samples != null) {
                  throw "found more than one smpl chunk";
                }

                bitsPerSample = 16;
                samples = ArrayInt16.fromReader(reader, size ~/ 2);

                break;

            case "sm24":
                // 24 bit audio is not supported.
                reader.skip(size);
                break;

            default:
                throw "The INFO list contains an unknown ID '$id'.";
        }
    }

    if (samples == null || bitsPerSample == null)
    {
        throw "No valid sample data was found.";
    }

    return SoundFontSampleData(bitsPerSample: bitsPerSample, samples: samples);

}