3pp-mirror/snapcast
1
0
Fork 0
mirror of https://github.com/badaix/snapcast.git synced 2025-05-29 08:56:18 +02:00
Code Issues Projects Releases Packages Wiki Activity

decoder gets sample format from header

Browse source
This commit is contained in:
badaix 2016-01-24 13:43:02 +01:00
parent 1d1ef239b2
commit eed7f287fb
10 changed files with 216 additions and 114 deletions
Download patch file Download diff file Expand all files Collapse all files

90
client/decoder/pcmDecoder.cpp
View file

@ -16,8 +16,42 @@
along with this program. If not, see <http://www.gnu.org/licenses/>.
***/
#include "common/snapException.h"
#include "common/log.h"
#include "pcmDecoder.h"
#define ID_RIFF 0x46464952
#define ID_WAVE 0x45564157
#define ID_FMT 0x20746d66
#define ID_DATA 0x61746164
struct riff_wave_header
{
uint32_t riff_id;
uint32_t riff_sz;
uint32_t wave_id;
};
struct chunk_header
{
uint32_t id;
uint32_t sz;
};
struct chunk_fmt
{
uint16_t audio_format;
uint16_t num_channels;
uint32_t sample_rate;
uint32_t byte_rate;
uint16_t block_align;
uint16_t bits_per_sample;
};
PcmDecoder::PcmDecoder() : Decoder()
{
}
@ -29,9 +63,61 @@ bool PcmDecoder::decode(msg::PcmChunk* chunk)
}
bool PcmDecoder::setHeader(msg::Header* chunk)
msg::SampleFormat PcmDecoder::setHeader(msg::Header* chunk)
{
return true;
if (chunk->payloadSize < 44)
throw SnapException("PCM header too small");
struct riff_wave_header riff_wave_header;
struct chunk_header chunk_header;
struct chunk_fmt chunk_fmt;
chunk_fmt.sample_rate = 0;
size_t pos(0);
memcpy(&riff_wave_header, chunk->payload + pos, sizeof(riff_wave_header));
pos += sizeof(riff_wave_header);
if ((riff_wave_header.riff_id != ID_RIFF) || (riff_wave_header.wave_id != ID_WAVE))
throw SnapException("Not a riff/wave header");
bool moreChunks(true);
do
{
if (pos + sizeof(chunk_header) > chunk->payloadSize)
throw SnapException("riff/wave header incomplete");
memcpy(&chunk_header, chunk->payload + pos, sizeof(chunk_header));
pos += sizeof(chunk_header);
switch (chunk_header.id)
{
case ID_FMT:
if (pos + sizeof(chunk_fmt) > chunk->payloadSize)
throw SnapException("riff/wave header incomplete");
memcpy(&chunk_fmt, chunk->payload + pos, sizeof(chunk_fmt));
pos += sizeof(chunk_fmt);
/// If the format header is larger, skip the rest
if (chunk_header.sz > sizeof(chunk_fmt))
pos += (chunk_header.sz - sizeof(chunk_fmt));
break;
case ID_DATA:
/// Stop looking for chunks
moreChunks = false;
break;
default:
/// Unknown chunk, skip bytes
pos += chunk_header.sz;
}
}
while (moreChunks);
if (chunk_fmt.sample_rate == 0)
throw SnapException("Sample format not found");
msg::SampleFormat sampleFormat(
chunk_fmt.sample_rate,
chunk_fmt.bits_per_sample,
chunk_fmt.num_channels);
return sampleFormat;
}