| /* |
| * 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. |
| * |
| * 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. |
| * |
| * 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 FFmpeg; if not, write to the Free Software |
| * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| */ |
| |
| /** |
| * @file |
| * 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 <gsm/gsm.h> |
| |
| #include "avcodec.h" |
| #include "gsm.h" |
| |
| static av_cold int libgsm_encode_init(AVCodecContext *avctx) { |
| if (avctx->channels > 1) { |
| av_log(avctx, AV_LOG_ERROR, "Mono required for GSM, got %d channels\n", |
| avctx->channels); |
| return -1; |
| } |
| |
| if (avctx->sample_rate != 8000) { |
| av_log(avctx, AV_LOG_ERROR, "Sample rate 8000Hz required for GSM, got %dHz\n", |
| avctx->sample_rate); |
| if (avctx->strict_std_compliance > FF_COMPLIANCE_UNOFFICIAL) |
| return -1; |
| } |
| if (avctx->bit_rate != 13000 /* Official */ && |
| avctx->bit_rate != 13200 /* Very common */ && |
| avctx->bit_rate != 0 /* Unknown; a.o. mov does not set bitrate when decoding */ ) { |
| av_log(avctx, AV_LOG_ERROR, "Bitrate 13000bps required for GSM, got %dbps\n", |
| avctx->bit_rate); |
| if (avctx->strict_std_compliance > FF_COMPLIANCE_UNOFFICIAL) |
| return -1; |
| } |
| |
| 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; |
| |
| return 0; |
| } |
| |
| static av_cold int libgsm_encode_close(AVCodecContext *avctx) { |
| av_freep(&avctx->coded_frame); |
| gsm_destroy(avctx->priv_data); |
| avctx->priv_data = NULL; |
| return 0; |
| } |
| |
| static int libgsm_encode_frame(AVCodecContext *avctx, |
| unsigned char *frame, int buf_size, void *data) { |
| // we need a full block |
| 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; |
| } |
| |
| |
| AVCodec ff_libgsm_encoder = { |
| .name = "libgsm", |
| .type = AVMEDIA_TYPE_AUDIO, |
| .id = CODEC_ID_GSM, |
| .init = libgsm_encode_init, |
| .encode = libgsm_encode_frame, |
| .close = libgsm_encode_close, |
| .sample_fmts = (const enum AVSampleFormat[]){AV_SAMPLE_FMT_S16,AV_SAMPLE_FMT_NONE}, |
| .long_name = NULL_IF_CONFIG_SMALL("libgsm GSM"), |
| }; |
| |
| AVCodec ff_libgsm_ms_encoder = { |
| .name = "libgsm_ms", |
| .type = AVMEDIA_TYPE_AUDIO, |
| .id = CODEC_ID_GSM_MS, |
| .init = libgsm_encode_init, |
| .encode = libgsm_encode_frame, |
| .close = libgsm_encode_close, |
| .sample_fmts = (const enum AVSampleFormat[]){AV_SAMPLE_FMT_S16,AV_SAMPLE_FMT_NONE}, |
| .long_name = NULL_IF_CONFIG_SMALL("libgsm GSM Microsoft variant"), |
| }; |
| |
| typedef struct LibGSMDecodeContext { |
| AVFrame frame; |
| struct gsm_state *state; |
| } LibGSMDecodeContext; |
| |
| static av_cold int libgsm_decode_init(AVCodecContext *avctx) { |
| LibGSMDecodeContext *s = avctx->priv_data; |
| |
| if (avctx->channels > 1) { |
| av_log(avctx, AV_LOG_ERROR, "Mono required for GSM, got %d channels\n", |
| avctx->channels); |
| return -1; |
| } |
| |
| if (!avctx->channels) |
| avctx->channels = 1; |
| |
| if (!avctx->sample_rate) |
| avctx->sample_rate = 8000; |
| |
| avctx->sample_fmt = AV_SAMPLE_FMT_S16; |
| |
| s->state = 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(s->state, GSM_OPT_WAV49, &one); |
| avctx->frame_size = 2 * GSM_FRAME_SIZE; |
| avctx->block_align = GSM_MS_BLOCK_SIZE; |
| } |
| } |
| |
| avcodec_get_frame_defaults(&s->frame); |
| avctx->coded_frame = &s->frame; |
| |
| return 0; |
| } |
| |
| static av_cold int libgsm_decode_close(AVCodecContext *avctx) { |
| LibGSMDecodeContext *s = avctx->priv_data; |
| |
| gsm_destroy(s->state); |
| s->state = NULL; |
| return 0; |
| } |
| |
| static int libgsm_decode_frame(AVCodecContext *avctx, void *data, |
| int *got_frame_ptr, AVPacket *avpkt) |
| { |
| int i, ret; |
| LibGSMDecodeContext *s = avctx->priv_data; |
| uint8_t *buf = avpkt->data; |
| int buf_size = avpkt->size; |
| int16_t *samples; |
| |
| if (buf_size < avctx->block_align) { |
| av_log(avctx, AV_LOG_ERROR, "Packet is too small\n"); |
| return AVERROR_INVALIDDATA; |
| } |
| |
| /* get output buffer */ |
| s->frame.nb_samples = avctx->frame_size; |
| if ((ret = avctx->get_buffer(avctx, &s->frame)) < 0) { |
| av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n"); |
| return ret; |
| } |
| samples = (int16_t *)s->frame.data[0]; |
| |
| for (i = 0; i < avctx->frame_size / GSM_FRAME_SIZE; i++) { |
| if ((ret = gsm_decode(s->state, buf, samples)) < 0) |
| return -1; |
| buf += GSM_BLOCK_SIZE; |
| samples += GSM_FRAME_SIZE; |
| } |
| |
| *got_frame_ptr = 1; |
| *(AVFrame *)data = s->frame; |
| |
| return avctx->block_align; |
| } |
| |
| static void libgsm_flush(AVCodecContext *avctx) { |
| LibGSMDecodeContext *s = avctx->priv_data; |
| int one = 1; |
| |
| gsm_destroy(s->state); |
| s->state = gsm_create(); |
| if (avctx->codec_id == CODEC_ID_GSM_MS) |
| gsm_option(s->state, GSM_OPT_WAV49, &one); |
| } |
| |
| AVCodec ff_libgsm_decoder = { |
| .name = "libgsm", |
| .type = AVMEDIA_TYPE_AUDIO, |
| .id = CODEC_ID_GSM, |
| .priv_data_size = sizeof(LibGSMDecodeContext), |
| .init = libgsm_decode_init, |
| .close = libgsm_decode_close, |
| .decode = libgsm_decode_frame, |
| .flush = libgsm_flush, |
| .capabilities = CODEC_CAP_DR1, |
| .long_name = NULL_IF_CONFIG_SMALL("libgsm GSM"), |
| }; |
| |
| AVCodec ff_libgsm_ms_decoder = { |
| .name = "libgsm_ms", |
| .type = AVMEDIA_TYPE_AUDIO, |
| .id = CODEC_ID_GSM_MS, |
| .priv_data_size = sizeof(LibGSMDecodeContext), |
| .init = libgsm_decode_init, |
| .close = libgsm_decode_close, |
| .decode = libgsm_decode_frame, |
| .flush = libgsm_flush, |
| .capabilities = CODEC_CAP_DR1, |
| .long_name = NULL_IF_CONFIG_SMALL("libgsm GSM Microsoft variant"), |
| }; |