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roqaudioenc: use AVCodecContext.frame_size correctly.

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It is not allowed to change mid-stream like it does currently. Instead we need
to buffer the first 8 frames before returning them as a single packet, then
only return single frame packets after that.
This commit is contained in:
Justin Ruggles 2012-02-22 16:20:49 -05:00
parent 56279f1d61
commit cf57c78b77
1 changed files with 65 additions and 26 deletions
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91
libavcodec/roqaudioenc.c
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@ -25,9 +25,8 @@
#include "avcodec.h"
#include "bytestream.h"
#define ROQ_FIRST_FRAME_SIZE (735*8)
#define ROQ_FRAME_SIZE 735
#define ROQ_HEADER_SIZE 8
#define MAX_DPCM (127*127)
@ -35,11 +34,26 @@
typedef struct
{
short lastSample[2];
int input_frames;
int buffered_samples;
int16_t *frame_buffer;
} ROQDPCMContext;
static av_cold int roq_dpcm_encode_close(AVCodecContext *avctx)
{
ROQDPCMContext *context = avctx->priv_data;
av_freep(&avctx->coded_frame);
av_freep(&context->frame_buffer);
return 0;
}
static av_cold int roq_dpcm_encode_init(AVCodecContext *avctx)
{
ROQDPCMContext *context = avctx->priv_data;
int ret;
if (avctx->channels > 2) {
av_log(avctx, AV_LOG_ERROR, "Audio must be mono or stereo\n");
@ -50,15 +64,27 @@ static av_cold int roq_dpcm_encode_init(AVCodecContext *avctx)
return -1;
}
avctx->frame_size = ROQ_FIRST_FRAME_SIZE;
avctx->frame_size = ROQ_FRAME_SIZE;
context->frame_buffer = av_malloc(8 * ROQ_FRAME_SIZE * avctx->channels *
sizeof(*context->frame_buffer));
if (!context->frame_buffer) {
ret = AVERROR(ENOMEM);
goto error;
}
context->lastSample[0] = context->lastSample[1] = 0;
avctx->coded_frame= avcodec_alloc_frame();
if (!avctx->coded_frame)
return AVERROR(ENOMEM);
if (!avctx->coded_frame) {
ret = AVERROR(ENOMEM);
goto error;
}
return 0;
error:
roq_dpcm_encode_close(avctx);
return ret;
}
static unsigned char dpcm_predict(short *previous, short current)
@ -104,25 +130,45 @@ static unsigned char dpcm_predict(short *previous, short current)
static int roq_dpcm_encode_frame(AVCodecContext *avctx,
unsigned char *frame, int buf_size, void *data)
{
int i, samples, stereo, ch;
const short *in;
unsigned char *out;
int i, stereo, data_size;
const int16_t *in = data;
uint8_t *out = frame;
ROQDPCMContext *context = avctx->priv_data;
stereo = (avctx->channels == 2);
if (!data && context->input_frames >= 8)
return 0;
if (data && context->input_frames < 8) {
memcpy(&context->frame_buffer[context->buffered_samples * avctx->channels],
in, avctx->frame_size * avctx->channels * sizeof(*in));
context->buffered_samples += avctx->frame_size;
if (context->input_frames < 7) {
context->input_frames++;
return 0;
}
in = context->frame_buffer;
}
if (stereo) {
context->lastSample[0] &= 0xFF00;
context->lastSample[1] &= 0xFF00;
}
out = frame;
in = data;
if (context->input_frames == 7 || !data)
data_size = avctx->channels * context->buffered_samples;
else
data_size = avctx->channels * avctx->frame_size;
if (buf_size < ROQ_HEADER_SIZE + data_size) {
av_log(avctx, AV_LOG_ERROR, "output buffer is too small\n");
return AVERROR(EINVAL);
}
bytestream_put_byte(&out, stereo ? 0x21 : 0x20);
bytestream_put_byte(&out, 0x10);
bytestream_put_le32(&out, avctx->frame_size*avctx->channels);
bytestream_put_le32(&out, data_size);
if (stereo) {
bytestream_put_byte(&out, (context->lastSample[1])>>8);
@ -131,23 +177,15 @@ static int roq_dpcm_encode_frame(AVCodecContext *avctx,
bytestream_put_le16(&out, context->lastSample[0]);
/* Write the actual samples */
samples = avctx->frame_size;
for (i=0; i<samples; i++)
for (ch=0; ch<avctx->channels; ch++)
*out++ = dpcm_predict(&context->lastSample[ch], *in++);
for (i = 0; i < data_size; i++)
*out++ = dpcm_predict(&context->lastSample[i & 1], *in++);
/* Use smaller frames from now on */
avctx->frame_size = ROQ_FRAME_SIZE;
context->input_frames++;
if (!data)
context->input_frames = FFMAX(context->input_frames, 8);
/* Return the result size */
return out - frame;
}
static av_cold int roq_dpcm_encode_close(AVCodecContext *avctx)
{
av_freep(&avctx->coded_frame);
return 0;
return ROQ_HEADER_SIZE + data_size;
}
AVCodec ff_roq_dpcm_encoder = {
@ -158,6 +196,7 @@ AVCodec ff_roq_dpcm_encoder = {
.init = roq_dpcm_encode_init,
.encode = roq_dpcm_encode_frame,
.close = roq_dpcm_encode_close,
.capabilities = CODEC_CAP_DELAY,
.sample_fmts = (const enum AVSampleFormat[]){AV_SAMPLE_FMT_S16,AV_SAMPLE_FMT_NONE},
.long_name = NULL_IF_CONFIG_SMALL("id RoQ DPCM"),
};