diff options
author | Michel Bardiaux <mbardiaux@mediaxim.be> | 2007-02-20 14:09:47 +0300 |
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committer | Michel Bardiaux <mbardiaux@mediaxim.be> | 2007-02-20 14:09:47 +0300 |
commit | 346a655d467915a2a96019104d6ec7cdd859f1f9 (patch) | |
tree | 8c1dca31249aaaf9442dc6fab22111de687ce6d5 /libavcodec/libgsm.c | |
parent | 758a6b3c061141af741c7dd777313f9d944ff86d (diff) |
Add support for MS-GSM codec
Originally committed as revision 8039 to svn://svn.ffmpeg.org/ffmpeg/trunk
Diffstat (limited to 'libavcodec/libgsm.c')
-rw-r--r-- | libavcodec/libgsm.c | 78 |
1 files changed, 63 insertions, 15 deletions
diff --git a/libavcodec/libgsm.c b/libavcodec/libgsm.c index 7cf59be7ac..86dfce575c 100644 --- a/libavcodec/libgsm.c +++ b/libavcodec/libgsm.c @@ -1,6 +1,7 @@ /* * Interface to libgsm for gsm encoding/decoding * Copyright (c) 2005 Alban Bedel <albeu@free.fr> + * Copyright (c) 2006, 2007 Michel Bardiaux <mbardiaux@mediaxim.be> * * This file is part of FFmpeg. * @@ -24,22 +25,35 @@ * Interface to libgsm for gsm encoding/decoding */ +// The idiosyncrasies of GSM-in-WAV are explained at http://kbs.cs.tu-berlin.de/~jutta/toast.html + #include "avcodec.h" #include <gsm.h> // gsm.h miss some essential constants #define GSM_BLOCK_SIZE 33 +#define GSM_MS_BLOCK_SIZE 65 #define GSM_FRAME_SIZE 160 static int libgsm_init(AVCodecContext *avctx) { - if (avctx->channels > 1 || avctx->sample_rate != 8000) + if (avctx->channels > 1 || avctx->sample_rate != 8000 || avctx->bit_rate != 13000) return -1; - avctx->frame_size = GSM_FRAME_SIZE; - avctx->block_align = GSM_BLOCK_SIZE; - avctx->priv_data = gsm_create(); + switch(avctx->codec_id) { + case CODEC_ID_GSM: + avctx->frame_size = GSM_FRAME_SIZE; + avctx->block_align = GSM_BLOCK_SIZE; + break; + case CODEC_ID_GSM_MS: { + int one = 1; + gsm_option(avctx->priv_data, GSM_OPT_WAV49, &one); + avctx->frame_size = 2*GSM_FRAME_SIZE; + avctx->block_align = GSM_MS_BLOCK_SIZE; + } + } + avctx->coded_frame= avcodec_alloc_frame(); avctx->coded_frame->key_frame= 1; @@ -55,11 +69,17 @@ static int libgsm_close(AVCodecContext *avctx) { static int libgsm_encode_frame(AVCodecContext *avctx, unsigned char *frame, int buf_size, void *data) { // we need a full block - if(buf_size < GSM_BLOCK_SIZE) return 0; - - gsm_encode(avctx->priv_data,data,frame); - - return GSM_BLOCK_SIZE; + if(buf_size < avctx->block_align) return 0; + + switch(avctx->codec_id) { + case CODEC_ID_GSM: + gsm_encode(avctx->priv_data,data,frame); + break; + case CODEC_ID_GSM_MS: + gsm_encode(avctx->priv_data,data,frame); + gsm_encode(avctx->priv_data,((short*)data)+GSM_FRAME_SIZE,frame+32); + } + return avctx->block_align; } @@ -73,16 +93,33 @@ AVCodec libgsm_encoder = { libgsm_close, }; +AVCodec libgsm_ms_encoder = { + "gsm", + CODEC_TYPE_AUDIO, + CODEC_ID_GSM_MS, + 0, + libgsm_init, + libgsm_encode_frame, + libgsm_close, +}; + static int libgsm_decode_frame(AVCodecContext *avctx, void *data, int *data_size, uint8_t *buf, int buf_size) { - if(buf_size < GSM_BLOCK_SIZE) return 0; - - if(gsm_decode(avctx->priv_data,buf,data)) return -1; - - *data_size = GSM_FRAME_SIZE*2; - return GSM_BLOCK_SIZE; + if(buf_size < avctx->block_align) return 0; + + switch(avctx->codec_id) { + case CODEC_ID_GSM: + if(gsm_decode(avctx->priv_data,buf,data)) return -1; + *data_size = GSM_FRAME_SIZE*sizeof(int16_t); + break; + case CODEC_ID_GSM_MS: + if(gsm_decode(avctx->priv_data,buf,data) || + gsm_decode(avctx->priv_data,buf+33,((int16_t*)data)+GSM_FRAME_SIZE)) return -1; + *data_size = GSM_FRAME_SIZE*sizeof(int16_t)*2; + } + return avctx->block_align; } AVCodec libgsm_decoder = { @@ -95,3 +132,14 @@ AVCodec libgsm_decoder = { libgsm_close, libgsm_decode_frame, }; + +AVCodec libgsm_ms_decoder = { + "gsm_ms", + CODEC_TYPE_AUDIO, + CODEC_ID_GSM_MS, + 0, + libgsm_init, + NULL, + libgsm_close, + libgsm_decode_frame, +}; |