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Diffstat (limited to 'ffmpeg/libavcodec/gsmdec.c')
| -rw-r--r-- | ffmpeg/libavcodec/gsmdec.c | 128 |
1 files changed, 128 insertions, 0 deletions
diff --git a/ffmpeg/libavcodec/gsmdec.c b/ffmpeg/libavcodec/gsmdec.c new file mode 100644 index 0000000..dc64267 --- /dev/null +++ b/ffmpeg/libavcodec/gsmdec.c @@ -0,0 +1,128 @@ +/* + * gsm 06.10 decoder + * Copyright (c) 2010 Reimar Döffinger <Reimar.Doeffinger@gmx.de> + * + * 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 + * GSM decoder + */ + +#include "libavutil/channel_layout.h" +#include "avcodec.h" +#include "get_bits.h" +#include "internal.h" +#include "msgsmdec.h" + +#include "gsmdec_template.c" + +static av_cold int gsm_init(AVCodecContext *avctx) +{ + avctx->channels = 1; + avctx->channel_layout = AV_CH_LAYOUT_MONO; + if (!avctx->sample_rate) + avctx->sample_rate = 8000; + avctx->sample_fmt = AV_SAMPLE_FMT_S16; + + switch (avctx->codec_id) { + case AV_CODEC_ID_GSM: + avctx->frame_size = GSM_FRAME_SIZE; + avctx->block_align = GSM_BLOCK_SIZE; + break; + case AV_CODEC_ID_GSM_MS: + avctx->frame_size = 2 * GSM_FRAME_SIZE; + avctx->block_align = GSM_MS_BLOCK_SIZE; + } + + return 0; +} + +static int gsm_decode_frame(AVCodecContext *avctx, void *data, + int *got_frame_ptr, AVPacket *avpkt) +{ + AVFrame *frame = data; + int res; + GetBitContext gb; + const 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 */ + frame->nb_samples = avctx->frame_size; + if ((res = ff_get_buffer(avctx, frame, 0)) < 0) + return res; + samples = (int16_t *)frame->data[0]; + + switch (avctx->codec_id) { + case AV_CODEC_ID_GSM: + init_get_bits(&gb, buf, buf_size * 8); + if (get_bits(&gb, 4) != 0xd) + av_log(avctx, AV_LOG_WARNING, "Missing GSM magic!\n"); + res = gsm_decode_block(avctx, samples, &gb); + if (res < 0) + return res; + break; + case AV_CODEC_ID_GSM_MS: + res = ff_msgsm_decode_block(avctx, samples, buf); + if (res < 0) + return res; + } + + *got_frame_ptr = 1; + + return avctx->block_align; +} + +static void gsm_flush(AVCodecContext *avctx) +{ + GSMContext *s = avctx->priv_data; + memset(s, 0, sizeof(*s)); +} + +#if CONFIG_GSM_DECODER +AVCodec ff_gsm_decoder = { + .name = "gsm", + .type = AVMEDIA_TYPE_AUDIO, + .id = AV_CODEC_ID_GSM, + .priv_data_size = sizeof(GSMContext), + .init = gsm_init, + .decode = gsm_decode_frame, + .flush = gsm_flush, + .capabilities = CODEC_CAP_DR1, + .long_name = NULL_IF_CONFIG_SMALL("GSM"), +}; +#endif +#if CONFIG_GSM_MS_DECODER +AVCodec ff_gsm_ms_decoder = { + .name = "gsm_ms", + .type = AVMEDIA_TYPE_AUDIO, + .id = AV_CODEC_ID_GSM_MS, + .priv_data_size = sizeof(GSMContext), + .init = gsm_init, + .decode = gsm_decode_frame, + .flush = gsm_flush, + .capabilities = CODEC_CAP_DR1, + .long_name = NULL_IF_CONFIG_SMALL("GSM Microsoft variant"), +}; +#endif |