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input/wav: Support for WAVE_FORMAT_EXTENSIBLE. 

This is needed for supporting > 16-bit PCM samples.
This commit is contained in:
Bert Vermeulen 2014-08-27 15:55:52 +02:00
parent 962d43440a
commit cbd9e6e987
1 changed files with 36 additions and 10 deletions
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46
src/input/wav.c
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@ -38,8 +38,9 @@
/* Expect to find the "data" chunk within this offset from the start. */
#define MAX_DATA_CHUNK_OFFSET 256
#define WAVE_FORMAT_PCM 1
#define WAVE_FORMAT_IEEE_FLOAT 3
#define WAVE_FORMAT_PCM 0x0001
#define WAVE_FORMAT_IEEE_FLOAT 0x0003
#define WAVE_FORMAT_EXTENSIBLE 0xfffe
struct context {
int fmt_code;
@ -53,29 +54,54 @@ struct context {
static int parse_wav_header(GString *buf, struct context *inc)
{
uint64_t samplerate;
int fmt_code, samplesize, num_channels, unitsize;
unsigned int fmt_code, samplesize, num_channels, unitsize;
if (buf->len < MIN_DATA_CHUNK_OFFSET) {
if (buf->len < MIN_DATA_CHUNK_OFFSET)
return SR_ERR;
}
fmt_code = RL16(buf->str + 20);
samplerate = RL32(buf->str + 24);
samplesize = RL16(buf->str + 32);
if (samplesize != 1 && samplesize != 2 && samplesize != 4) {
sr_err("Only 8, 16 or 32 bits per sample supported.");
return SR_ERR;
}
num_channels = RL16(buf->str + 22);
/* TODO div0 */
if (num_channels == 0)
return SR_ERR;
unitsize = samplesize / num_channels;
if (fmt_code == WAVE_FORMAT_PCM) {
if (samplesize != 1 && samplesize != 2 && samplesize != 4) {
sr_err("only 8, 16 or 32 bits per sample supported.");
return SR_ERR;
}
} else if (fmt_code == WAVE_FORMAT_IEEE_FLOAT) {
if (unitsize != 4) {
sr_err("only 32-bit floats supported.");
return SR_ERR;
}
} else if (fmt_code == WAVE_FORMAT_EXTENSIBLE) {
if (buf->len < 70)
/* Not enough for extensible header and next chunk. */
return SR_OK_CONTINUE;
if (RL16(buf->str + 16) != 40) {
sr_err("WAV extensible format chunk must be 40 bytes.");
return SR_ERR;
}
if (RL16(buf->str + 36) != 22) {
sr_err("WAV extension must be 22 bytes.");
return SR_ERR;
}
if (RL16(buf->str + 34) != RL16(buf->str + 38)) {
sr_err("Reduced valid bits per sample not supported.");
return SR_ERR;
}
/* Real format code is the first two bytes of the GUID. */
fmt_code = RL16(buf->str + 44);
if (fmt_code != WAVE_FORMAT_PCM && fmt_code != WAVE_FORMAT_IEEE_FLOAT) {
sr_err("Only PCM and floating point samples are supported.");
return SR_ERR;
}
} else {
sr_err("Only PCM and floating point samples are supported.");
return SR_ERR;