* This is a very straightforward rendition of the G.726
* Section 4 "Computational Details".
*
- * This file is part of FFmpeg.
+ * This file is part of Libav.
*
- * FFmpeg is free software; you can redistribute it and/or
+ * Libav 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.
*
- * FFmpeg is distributed in the hope that it will be useful,
+ * Libav 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 FFmpeg; if not, write to the Free Software
+ * License along with Libav; 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/channel_layout.h"
+#include "libavutil/opt.h"
#include "avcodec.h"
-#include "bitstream.h"
+#include "internal.h"
+#include "get_bits.h"
+#include "put_bits.h"
/**
* G.726 11bit float.
* G.726 Standard uses rather odd 11bit floating point arithmentic for
- * numerous occasions. It's a mistery to me why they did it this way
+ * numerous occasions. It's a mystery to me why they did it this way
* instead of simply using 32bit integer arithmetic.
*/
typedef struct Float11 {
} G726Tables;
typedef struct G726Context {
+ AVClass *class;
+ AVFrame frame;
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);
+
+#if FF_API_OLD_ENCODE_AUDIO
avctx->coded_frame = avcodec_alloc_frame();
if (!avctx->coded_frame)
return AVERROR(ENOMEM);
avctx->coded_frame->key_frame = 1;
+#endif
- if (avctx->codec->decode)
- avctx->sample_fmt = SAMPLE_FMT_S16;
+ /* select a frame size that will end on a byte boundary and have a size of
+ approximately 1024 bytes */
+ avctx->frame_size = ((int[]){ 4096, 2736, 2048, 1640 })[c->code_size - 2];
return 0;
}
-static av_cold int g726_close(AVCodecContext *avctx)
+#if FF_API_OLD_ENCODE_AUDIO
+static av_cold int g726_encode_close(AVCodecContext *avctx)
{
av_freep(&avctx->coded_frame);
return 0;
}
+#endif
-#if CONFIG_ADPCM_G726_ENCODER
-static int g726_encode_frame(AVCodecContext *avctx,
- uint8_t *dst, int buf_size, void *data)
+static int g726_encode_frame(AVCodecContext *avctx, AVPacket *avpkt,
+ const AVFrame *frame, int *got_packet_ptr)
{
G726Context *c = avctx->priv_data;
- short *samples = data;
+ const int16_t *samples = (const int16_t *)frame->data[0];
PutBitContext pb;
+ int i, ret, out_size;
- init_put_bits(&pb, dst, 1024*1024);
+ out_size = (frame->nb_samples * c->code_size + 7) / 8;
+ if ((ret = ff_alloc_packet(avpkt, out_size))) {
+ av_log(avctx, AV_LOG_ERROR, "Error getting output packet\n");
+ return ret;
+ }
+ init_put_bits(&pb, avpkt->data, avpkt->size);
- for (; buf_size; buf_size--)
+ for (i = 0; i < frame->nb_samples; i++)
put_bits(&pb, c->code_size, g726_encode(c, *samples++));
flush_put_bits(&pb);
- return put_bits_count(&pb)>>3;
+ avpkt->size = out_size;
+ *got_packet_ptr = 1;
+ return 0;
}
+
+#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, { .i64 = 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 = AV_CODEC_ID_ADPCM_G726,
+ .priv_data_size = sizeof(G726Context),
+ .init = g726_encode_init,
+ .encode2 = g726_encode_frame,
+#if FF_API_OLD_ENCODE_AUDIO
+ .close = g726_encode_close,
+#endif
+ .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
-static int g726_decode_frame(AVCodecContext *avctx,
- void *data, int *data_size,
- AVPacket *avpkt)
+#if CONFIG_ADPCM_G726_DECODER
+static av_cold int g726_decode_init(AVCodecContext *avctx)
+{
+ G726Context* c = avctx->priv_data;
+
+ avctx->channels = 1;
+ avctx->channel_layout = AV_CH_LAYOUT_MONO;
+
+ 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;
+
+ avcodec_get_frame_defaults(&c->frame);
+ avctx->coded_frame = &c->frame;
+
+ return 0;
+}
+
+static int g726_decode_frame(AVCodecContext *avctx, void *data,
+ int *got_frame_ptr, AVPacket *avpkt)
{
const uint8_t *buf = avpkt->data;
int buf_size = avpkt->size;
G726Context *c = avctx->priv_data;
- short *samples = data;
+ int16_t *samples;
GetBitContext gb;
+ int out_samples, ret;
+
+ out_samples = buf_size * 8 / c->code_size;
+
+ /* get output buffer */
+ c->frame.nb_samples = out_samples;
+ if ((ret = ff_get_buffer(avctx, &c->frame)) < 0) {
+ av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
+ return ret;
+ }
+ samples = (int16_t *)c->frame.data[0];
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;
+ *got_frame_ptr = 1;
+ *(AVFrame *)data = c->frame;
+
return buf_size;
}
-#if CONFIG_ADPCM_G726_ENCODER
-AVCodec adpcm_g726_encoder = {
- "g726",
- CODEC_TYPE_AUDIO,
- CODEC_ID_ADPCM_G726,
- sizeof(G726Context),
- g726_init,
- g726_encode_frame,
- g726_close,
- NULL,
- .sample_fmts = (enum SampleFormat[]){SAMPLE_FMT_S16,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 adpcm_g726_decoder = {
- "g726",
- CODEC_TYPE_AUDIO,
- CODEC_ID_ADPCM_G726,
- sizeof(G726Context),
- g726_init,
- NULL,
- g726_close,
- g726_decode_frame,
- .long_name = NULL_IF_CONFIG_SMALL("G.726 ADPCM"),
+AVCodec ff_adpcm_g726_decoder = {
+ .name = "g726",
+ .type = AVMEDIA_TYPE_AUDIO,
+ .id = AV_CODEC_ID_ADPCM_G726,
+ .priv_data_size = sizeof(G726Context),
+ .init = g726_decode_init,
+ .decode = g726_decode_frame,
+ .flush = g726_decode_flush,
+ .capabilities = CODEC_CAP_DR1,
+ .long_name = NULL_IF_CONFIG_SMALL("G.726 ADPCM"),
};
+#endif
projects / ffmpeg / blobdiff