* This is a very straightforward rendition of the G.726
* Section 4 "Computational Details".
*
- * This file is part of Libav.
+ * This file is part of FFmpeg.
*
- * Libav is free software; you can redistribute it and/or
+ * FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
- * Libav is distributed in the hope that it will be useful,
+ * FFmpeg 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
- * License along with Libav; if not, write to the Free Software
+ * License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#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"
} G726Tables;
typedef struct G726Context {
+ AVClass *class;
G726Tables tbls; /**< static tables needed for computation */
Float11 sr[2]; /**< prev. reconstructed samples */
return av_clip(re_signal << 2, -0xffff, 0xffff);
}
-static av_cold int g726_reset(G726Context* c, int index)
+static av_cold int g726_reset(G726Context *c)
{
int i;
- c->tbls = G726Tables_pool[index];
+ c->tbls = G726Tables_pool[c->code_size - 2];
for (i=0; i<2; i++) {
c->sr[i].mant = 1<<5;
c->pk[i] = 1;
g726_decode(c, i);
return i;
}
-#endif
/* Interfacing to the libavcodec */
-static av_cold int g726_init(AVCodecContext * avctx)
+static av_cold int g726_encode_init(AVCodecContext *avctx)
{
G726Context* c = avctx->priv_data;
- unsigned int index;
- if (avctx->sample_rate <= 0) {
- av_log(avctx, AV_LOG_ERROR, "Samplerate is invalid\n");
- return -1;
+ if (avctx->strict_std_compliance > FF_COMPLIANCE_UNOFFICIAL &&
+ avctx->sample_rate != 8000) {
+ av_log(avctx, AV_LOG_ERROR, "Sample rates other than 8kHz are not "
+ "allowed when the compliance level is higher than unofficial. "
+ "Resample or reduce the compliance level.\n");
+ return AVERROR(EINVAL);
}
+ av_assert0(avctx->sample_rate > 0);
- index = (avctx->bit_rate + avctx->sample_rate/2) / avctx->sample_rate - 2;
-
- if (avctx->bit_rate % avctx->sample_rate && avctx->codec->encode) {
- av_log(avctx, AV_LOG_ERROR, "Bitrate - Samplerate combination is invalid\n");
- return -1;
- }
if(avctx->channels != 1){
av_log(avctx, AV_LOG_ERROR, "Only mono is supported\n");
- return -1;
- }
- if(index>3){
- av_log(avctx, AV_LOG_ERROR, "Unsupported number of bits %d\n", index+2);
- return -1;
+ return AVERROR(EINVAL);
}
- g726_reset(c, index);
- c->code_size = index+2;
+
+ 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);
avctx->coded_frame = avcodec_alloc_frame();
if (!avctx->coded_frame)
return AVERROR(ENOMEM);
avctx->coded_frame->key_frame = 1;
- if (avctx->codec->decode)
- avctx->sample_fmt = AV_SAMPLE_FMT_S16;
-
/* select a frame size that will end on a byte boundary and have a size of
approximately 1024 bytes */
- if (avctx->codec->encode)
- avctx->frame_size = ((int[]){ 4096, 2736, 2048, 1640 })[index];
+ avctx->frame_size = ((int[]){ 4096, 2736, 2048, 1640 })[c->code_size - 2];
return 0;
}
-static av_cold int g726_close(AVCodecContext *avctx)
+static av_cold int g726_encode_close(AVCodecContext *avctx)
{
av_freep(&avctx->coded_frame);
return 0;
}
-#if CONFIG_ADPCM_G726_ENCODER
static int g726_encode_frame(AVCodecContext *avctx,
uint8_t *dst, int buf_size, void *data)
{
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,
+ .id = CODEC_ID_ADPCM_G726,
+ .priv_data_size = sizeof(G726Context),
+ .init = g726_encode_init,
+ .encode = g726_encode_frame,
+ .close = g726_encode_close,
+ .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
+#if CONFIG_ADPCM_G726_DECODER
+static av_cold int g726_decode_init(AVCodecContext *avctx)
+{
+ G726Context* c = avctx->priv_data;
+
+ if (avctx->strict_std_compliance >= FF_COMPLIANCE_STRICT &&
+ avctx->sample_rate != 8000) {
+ av_log(avctx, AV_LOG_ERROR, "Only 8kHz sample rate is allowed when "
+ "the compliance level is strict. Reduce the compliance level "
+ "if you wish to decode the stream anyway.\n");
+ return AVERROR(EINVAL);
+ }
+
+ if(avctx->channels != 1){
+ av_log(avctx, AV_LOG_ERROR, "Only mono is supported\n");
+ return AVERROR(EINVAL);
+ }
+
+ c->code_size = avctx->bits_per_coded_sample;
+ 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);
+ }
+ g726_reset(c);
+
+ avctx->sample_fmt = AV_SAMPLE_FMT_S16;
+
+ return 0;
+}
+
static int g726_decode_frame(AVCodecContext *avctx,
void *data, int *data_size,
AVPacket *avpkt)
G726Context *c = avctx->priv_data;
int16_t *samples = data;
GetBitContext gb;
+ int out_samples, out_size;
+
+ out_samples = buf_size * 8 / c->code_size;
+ out_size = out_samples * av_get_bytes_per_sample(avctx->sample_fmt);
+ if (*data_size < out_size) {
+ av_log(avctx, AV_LOG_ERROR, "Output buffer is too small\n");
+ return AVERROR(EINVAL);
+ }
init_get_bits(&gb, buf, buf_size * 8);
- while (get_bits_count(&gb) + c->code_size <= buf_size*8)
+ while (out_samples--)
*samples++ = g726_decode(c, get_bits(&gb, c->code_size));
- if(buf_size*8 != get_bits_count(&gb))
+ if (get_bits_left(&gb) > 0)
av_log(avctx, AV_LOG_ERROR, "Frame invalidly split, missing parser?\n");
- *data_size = (uint8_t*)samples - (uint8_t*)data;
+ *data_size = out_size;
return buf_size;
}
-#if CONFIG_ADPCM_G726_ENCODER
-AVCodec ff_adpcm_g726_encoder = {
- .name = "g726",
- .type = AVMEDIA_TYPE_AUDIO,
- .id = CODEC_ID_ADPCM_G726,
- .priv_data_size = sizeof(G726Context),
- .init = g726_init,
- .encode = g726_encode_frame,
- .close = g726_close,
- .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"),
-};
-#endif
+static void g726_decode_flush(AVCodecContext *avctx)
+{
+ G726Context *c = avctx->priv_data;
+ g726_reset(c);
+}
AVCodec ff_adpcm_g726_decoder = {
.name = "g726",
.type = AVMEDIA_TYPE_AUDIO,
.id = CODEC_ID_ADPCM_G726,
.priv_data_size = sizeof(G726Context),
- .init = g726_init,
- .close = g726_close,
+ .init = g726_decode_init,
.decode = g726_decode_frame,
+ .flush = g726_decode_flush,
.long_name = NULL_IF_CONFIG_SMALL("G.726 ADPCM"),
};
+#endif
projects / ffmpeg / blobdiff