g726enc: add private option for setting code size directly.

This is an easy alternative to setting bit_rate. This patch also selects the
closest bit_rate to the requested one rather than requiring an exact value.
This commit is contained in:
Justin Ruggles 2011-10-27 21:19:41 -04:00
parent 7abb73d4ba
commit 615b2a2cf5

View File

@ -23,7 +23,9 @@
*/
#include <limits.h>
#include "libavutil/avassert.h"
#include "libavutil/opt.h"
#include "avcodec.h"
#include "internal.h"
#include "get_bits.h"
#include "put_bits.h"
@ -72,6 +74,7 @@ typedef struct G726Tables {
} G726Tables;
typedef struct G726Context {
AVClass *class;
G726Tables tbls; /**< static tables needed for computation */
Float11 sr[2]; /**< prev. reconstructed samples */
@ -317,15 +320,11 @@ static av_cold int g726_encode_init(AVCodecContext *avctx)
return AVERROR(EINVAL);
}
if (avctx->bit_rate % avctx->sample_rate) {
av_log(avctx, AV_LOG_ERROR, "Bitrate - Samplerate combination is invalid\n");
return AVERROR(EINVAL);
}
c->code_size = (avctx->bit_rate + avctx->sample_rate/2) / avctx->sample_rate;
if (c->code_size < 2 || c->code_size > 5) {
av_log(avctx, AV_LOG_ERROR, "Invalid number of bits %d\n", c->code_size);
return AVERROR(EINVAL);
}
if (avctx->bit_rate)
c->code_size = (avctx->bit_rate + avctx->sample_rate/2) / avctx->sample_rate;
c->code_size = av_clip(c->code_size, 2, 5);
avctx->bit_rate = c->code_size * avctx->sample_rate;
avctx->bits_per_coded_sample = c->code_size;
g726_reset(c, c->code_size - 2);
@ -366,6 +365,25 @@ static int g726_encode_frame(AVCodecContext *avctx,
return put_bits_count(&pb)>>3;
}
#define OFFSET(x) offsetof(G726Context, x)
#define AE AV_OPT_FLAG_AUDIO_PARAM | AV_OPT_FLAG_ENCODING_PARAM
static const AVOption options[] = {
{ "code_size", "Bits per code", OFFSET(code_size), AV_OPT_TYPE_INT, { 4 }, 2, 5, AE },
{ NULL },
};
static const AVClass class = {
.class_name = "g726",
.item_name = av_default_item_name,
.option = options,
.version = LIBAVUTIL_VERSION_INT,
};
static const AVCodecDefault defaults[] = {
{ "b", "0" },
{ NULL },
};
AVCodec ff_adpcm_g726_encoder = {
.name = "g726",
.type = AVMEDIA_TYPE_AUDIO,
@ -377,6 +395,8 @@ AVCodec ff_adpcm_g726_encoder = {
.capabilities = CODEC_CAP_SMALL_LAST_FRAME,
.sample_fmts = (const enum AVSampleFormat[]){AV_SAMPLE_FMT_S16,AV_SAMPLE_FMT_NONE},
.long_name = NULL_IF_CONFIG_SMALL("G.726 ADPCM"),
.priv_class = &class,
.defaults = defaults,
};
#endif