Enum DataFormat

pub enum DataFormat {
    Unspecified,
    Pcm,
    Adpcm(AdpcmSubFormat),
    PcmALaw,
    PcmMuLaw,
    Mp3(Mp3EncoderOptions),
    Opus(OpusEncoderOptions),
    Flac(FlacEncoderParams),
    OggVorbis(OggVorbisEncoderParams),
}

• Specify the audio codecs of the WAV file.

Variants

Unspecified

• This is used for creating a new DataFormat to specify an unknown format.

Pcm

• PCM format, supports u8, i16, i24, i32, f32, f64 for WAV, supports channel number >= 2, no compresion, lossless.

Adpcm(AdpcmSubFormat)

• ADPCM format, every sample stores as nibbles (One 4-bit nibble for a 16-bit sample), max channels is 2, lossy. Good for voice chatting, and very small memory usage.

PcmALaw

• PCM-aLaw, every sample stores as a byte (One byte for a 16-bit sample), max channels is 2, lossy. Encoding/decoding is by table lookup. These tables are not that small.
• Kind of useless. I prefer just to use the plain u8 PCM format to replace it. My supreme audio card can handle my u8 PCM and the playback is just as perfect as i16 does.

PcmMuLaw

• PCM-MuLaw. Not much different than the PCM-aLaw. Uses a different algorithm to encode.

Mp3(Mp3EncoderOptions)

• MP3. Just a pure MP3 file encapsulated in the data chunk. It needs some extra extension data in the fmt chunk.
• With the help of the WAV fmt chunk, you can get the spec of the audio file without decoding it first.
• The WAV file which encapsulates the MP3 file as its content, the size of the WAV file looks like an MP3 file size.

Opus(OpusEncoderOptions)

• Naked opus stream, without the Ogg container. The encoded data is stored as blocks in the data chunk, the block size is stored in the fmt chunk.
• Just take a look at the blocks, there are lots of zero bytes at the end, indicating that the Opus format is excellent at compressing the audio data.
• But WAV can’t get rid of these zero bytes, resulting in the compression ratio just like encoding each sample into a byte.
• Opus was originally designed for low-lag digital audio transmission with good quality. Encapsulating this thing into a WAV file is very weird.

Flac(FlacEncoderParams)

• FLAC. Just a pure FLAC file encapsulated in the data chunk.
• With the help of the WAV fmt chunk, you can get the spec of the audio file without decoding it first.
• The WAV file which encapsulates the FLAC file as its content, the size of the WAV file looks like an FLAC file size.

OggVorbis(OggVorbisEncoderParams)

• OggVorbis. Just a pure OggVorbis file encapsulated in the data chunk.
• The WAV file which encapsulates the OggVorbis file as its content, the size of the WAV file looks like an OggVorbis file size.

Trait Implementations

impl Clone for DataFormat

fn clone(&self) -> DataFormat

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for DataFormat

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Display for DataFormat

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl PartialEq for DataFormat

fn eq(&self, other: &DataFormat) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl StructuralPartialEq for DataFormat