snapcast/server/flacEncoder.cpp
2015-02-22 09:39:12 +01:00

213 lines
6.9 KiB
C++

/***
This file is part of snapcast
Copyright (C) 2015 Johannes Pohl
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
***/
#include "flacEncoder.h"
#include "common/log.h"
#include <iostream>
using namespace std;
#define READSIZE 16384
static FLAC__int32 pcm[READSIZE/*samples*/ * 2/*channels*/];
size_t encodedSamples = 0;
static msg::PcmChunk* encodedChunk = NULL;
FlacEncoder::FlacEncoder(const msg::SampleFormat& format) : Encoder(format), encoder(NULL)
{
encodedChunk = new msg::PcmChunk();
headerChunk = new msg::Header("flac");
initEncoder();
}
FlacEncoder::~FlacEncoder()
{
if (encoder != NULL)
{
FLAC__stream_encoder_finish(encoder);
FLAC__metadata_object_delete(metadata[0]);
FLAC__metadata_object_delete(metadata[1]);
FLAC__stream_encoder_delete(encoder);
}
delete encodedChunk;
}
msg::Header* FlacEncoder::getHeaderChunk()
{
return headerChunk;
}
double FlacEncoder::encode(msg::PcmChunk* chunk)
{
logD << "payload: " << chunk->payloadSize << "\tsamples: " << chunk->payloadSize/4 << "\n";
int samples = chunk->payloadSize / 4;
for(int i=0; i<samples*2/*channels*/; i++)
{
pcm[i] = (FLAC__int32)(((FLAC__int16)(FLAC__int8)chunk->payload[2*i+1] << 8) | (FLAC__int16)(0x00ff&chunk->payload[2*i]));
}
FLAC__stream_encoder_process_interleaved(encoder, pcm, samples);
double res = encodedSamples / ((double)sampleFormat.rate / 1000.);
if (encodedSamples > 0)
{
logD << "encoded: " << chunk->payloadSize << "\tsamples: " << encodedSamples << "\tres: " << res << "\n";
encodedSamples = 0;
chunk->payloadSize = encodedChunk->payloadSize;
chunk->payload = (char*)realloc(chunk->payload, encodedChunk->payloadSize);
memcpy(chunk->payload, encodedChunk->payload, encodedChunk->payloadSize);
encodedChunk->payloadSize = 0;
encodedChunk->payload = (char*)realloc(encodedChunk->payload, 0);
}
return res;//chunk->duration<chronos::msec>().count();
}
FLAC__StreamEncoderWriteStatus write_callback(const FLAC__StreamEncoder *encoder,
const FLAC__byte buffer[],
size_t bytes,
unsigned samples,
unsigned current_frame,
void *client_data)
{
logD << "write_callback: " << bytes << ", " << samples << ", " << current_frame << "\n";
FlacEncoder* flacEncoder = (FlacEncoder*)client_data;
if ((current_frame == 0) && (bytes > 0) && (samples == 0))
{
msg::Header* headerChunk = flacEncoder->getHeaderChunk();
headerChunk->payload = (char*)realloc(headerChunk->payload, headerChunk->payloadSize + bytes);
memcpy(headerChunk->payload + headerChunk->payloadSize, buffer, bytes);
headerChunk->payloadSize += bytes;
}
else
{
encodedChunk->payload = (char*)realloc(encodedChunk->payload, encodedChunk->payloadSize + bytes);
memcpy(encodedChunk->payload + encodedChunk->payloadSize, buffer, bytes);
encodedChunk->payloadSize += bytes;
encodedSamples += samples;
}
return FLAC__STREAM_ENCODER_WRITE_STATUS_OK;
}
void FlacEncoder::initEncoder()
{
FLAC__bool ok = true;
FLAC__StreamEncoderInitStatus init_status;
FLAC__StreamMetadata_VorbisComment_Entry entry;
// allocate the encoder
if((encoder = FLAC__stream_encoder_new()) == NULL) {
fprintf(stderr, "ERROR: allocating encoder\n");
return;
}
ok &= FLAC__stream_encoder_set_verify(encoder, true);
ok &= FLAC__stream_encoder_set_compression_level(encoder, 5);
ok &= FLAC__stream_encoder_set_channels(encoder, sampleFormat.channels);
ok &= FLAC__stream_encoder_set_bits_per_sample(encoder, sampleFormat.bits);
ok &= FLAC__stream_encoder_set_sample_rate(encoder, sampleFormat.rate);
// now add some metadata; we'll add some tags and a padding block
if(ok) {
if(
(metadata[0] = FLAC__metadata_object_new(FLAC__METADATA_TYPE_VORBIS_COMMENT)) == NULL ||
(metadata[1] = FLAC__metadata_object_new(FLAC__METADATA_TYPE_PADDING)) == NULL ||
// there are many tag (vorbiscomment) functions but these are convenient for this particular use:
!FLAC__metadata_object_vorbiscomment_entry_from_name_value_pair(&entry, "ARTIST", "Some Artist") ||
!FLAC__metadata_object_vorbiscomment_append_comment(metadata[0], entry, false) ||
!FLAC__metadata_object_vorbiscomment_entry_from_name_value_pair(&entry, "YEAR", "1984") ||
!FLAC__metadata_object_vorbiscomment_append_comment(metadata[0], entry, false)
) {
fprintf(stderr, "ERROR: out of memory or tag error\n");
ok = false;
}
metadata[1]->length = 1234; // set the padding length
ok = FLAC__stream_encoder_set_metadata(encoder, metadata, 2);
}
// initialize encoder
if(ok) {
init_status = FLAC__stream_encoder_init_stream(encoder, write_callback, NULL, NULL, NULL, this);
if(init_status != FLAC__STREAM_ENCODER_INIT_STATUS_OK) {
fprintf(stderr, "ERROR: initializing encoder: %s\n", FLAC__StreamEncoderInitStatusString[init_status]);
ok = false;
}
}
/*
// read blocks of samples from WAVE file and feed to encoder
if(ok) {
size_t left = (size_t)total_samples;
while(ok && left) {
size_t need = (left>READSIZE? (size_t)READSIZE : (size_t)left);
if(fread(buffer, channels*(bps/8), need, fin) != need) {
fprintf(stderr, "ERROR: reading from WAVE file\n");
ok = false;
}
else {
// convert the packed little-endian 16-bit PCM samples from WAVE into an interleaved FLAC__int32 buffer for libFLAC
size_t i;
for(i = 0; i < need*channels; i++) {
// inefficient but simple and works on big- or little-endian machines
pcm[i] = (FLAC__int32)(((FLAC__int16)(FLAC__int8)buffer[2*i+1] << 8) | (FLAC__int16)buffer[2*i]);
}
// feed samples to encoder
ok = FLAC__stream_encoder_process_interleaved(encoder, pcm, need);
}
left -= need;
}
}
ok &= FLAC__stream_encoder_finish(encoder);
fprintf(stderr, "encoding: %s\n", ok? "succeeded" : "FAILED");
fprintf(stderr, " state: %s\n", FLAC__StreamEncoderStateString[FLAC__stream_encoder_get_state(encoder)]);
// now that encoding is finished, the metadata can be freed
FLAC__metadata_object_delete(metadata[0]);
FLAC__metadata_object_delete(metadata[1]);
FLAC__stream_encoder_delete(encoder);
fclose(fin);
return 0;
*/
}
/*
void progress_callback(const FLAC__StreamEncoder *encoder, FLAC__uint64 bytes_written, FLAC__uint64 samples_written, unsigned frames_written, unsigned total_frames_estimate, void *client_data)
{
(void)encoder, (void)client_data;
fprintf(stderr, "wrote %d bytes, %d, %u samples, %u/%u frames\n", bytes_written, samples_written, total_samples, frames_written, total_frames_estimate);
}
*/