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flacenc: use a separate buffer for byte-swapping for MD5 checksum on big-endian

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This is much faster than calculating the MD5 one sample at a time.
This commit is contained in:
Justin Ruggles 2012-10-25 15:00:10 -04:00
parent 2253df76c1
commit 6a744d2619
1 changed files with 28 additions and 9 deletions
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37
libavcodec/flacenc.c
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@ -23,6 +23,7 @@
#include "libavutil/md5.h"
#include "libavutil/opt.h"
#include "avcodec.h"
#include "dsputil.h"
#include "get_bits.h"
#include "golomb.h"
#include "internal.h"
@ -100,6 +101,9 @@ typedef struct FlacEncodeContext {
AVCodecContext *avctx;
LPCContext lpc_ctx;
struct AVMD5 *md5ctx;
uint8_t *md5_buffer;
unsigned int md5_buffer_size;
DSPContext dsp;
} FlacEncodeContext;
@ -378,6 +382,8 @@ static av_cold int flac_encode_init(AVCodecContext *avctx)
ret = ff_lpc_init(&s->lpc_ctx, avctx->frame_size,
s->options.max_prediction_order, FF_LPC_TYPE_LEVINSON);
ff_dsputil_init(&s->dsp, avctx);
dprint_compression_options(s);
return ret;
@ -1176,17 +1182,26 @@ static int write_frame(FlacEncodeContext *s, AVPacket *avpkt)
}
static void update_md5_sum(FlacEncodeContext *s, const int16_t *samples)
static int update_md5_sum(FlacEncodeContext *s, const int16_t *samples)
{
#if HAVE_BIGENDIAN
int i;
for (i = 0; i < s->frame.blocksize * s->channels; i++) {
int16_t smp = av_le2ne16(samples[i]);
av_md5_update(s->md5ctx, (uint8_t *)&smp, 2);
const uint8_t *buf;
int buf_size = s->frame.blocksize * s->channels * 2;
if (HAVE_BIGENDIAN) {
av_fast_malloc(&s->md5_buffer, &s->md5_buffer_size, buf_size);
if (!s->md5_buffer)
return AVERROR(ENOMEM);
}
#else
av_md5_update(s->md5ctx, (const uint8_t *)samples, s->frame.blocksize*s->channels*2);
buf = (const uint8_t *)samples;
#if HAVE_BIGENDIAN
s->dsp.bswap16_buf((uint16_t *)s->md5_buffer,
(const uint16_t *)samples, buf_size / 2);
buf = s->md5_buffer;
#endif
av_md5_update(s->md5ctx, buf, buf_size);
return 0;
}
@ -1238,7 +1253,10 @@ static int flac_encode_frame(AVCodecContext *avctx, AVPacket *avpkt,
s->frame_count++;
s->sample_count += frame->nb_samples;
update_md5_sum(s, samples);
if ((ret = update_md5_sum(s, samples)) < 0) {
av_log(avctx, AV_LOG_ERROR, "Error updating MD5 checksum\n");
return ret;
}
if (out_bytes > s->max_encoded_framesize)
s->max_encoded_framesize = out_bytes;
if (out_bytes < s->min_framesize)
@ -1257,6 +1275,7 @@ static av_cold int flac_encode_close(AVCodecContext *avctx)
if (avctx->priv_data) {
FlacEncodeContext *s = avctx->priv_data;
av_freep(&s->md5ctx);
av_freep(&s->md5_buffer);
ff_lpc_end(&s->lpc_ctx);
}
av_freep(&avctx->extradata);