From b4edbe9a0eb48423fbf249b0ca7fb62838bdb7f5 Mon Sep 17 00:00:00 2001 From: Nidhi Makhijani Date: Tue, 8 Jul 2014 09:03:35 +0530 Subject: libgsm: Split decoder and encoder Signed-off-by: Diego Biurrun --- libavcodec/libgsmenc.c | 137 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 137 insertions(+) create mode 100644 libavcodec/libgsmenc.c (limited to 'libavcodec/libgsmenc.c') diff --git a/libavcodec/libgsmenc.c b/libavcodec/libgsmenc.c new file mode 100644 index 0000000000..8f51321d46 --- /dev/null +++ b/libavcodec/libgsmenc.c @@ -0,0 +1,137 @@ +/* + * Interface to libgsm for GSM encoding + * Copyright (c) 2005 Alban Bedel + * Copyright (c) 2006, 2007 Michel Bardiaux + * + * This file is part of Libav. + * + * 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. + * + * 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 Libav; 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 + */ + +// The idiosyncrasies of GSM-in-WAV are explained at http://kbs.cs.tu-berlin.de/~jutta/toast.html + +#include "config.h" +#if HAVE_GSM_H +#include +#else +#include +#endif + +#include "libavutil/common.h" + +#include "avcodec.h" +#include "internal.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 AV_CODEC_ID_GSM: + avctx->frame_size = GSM_FRAME_SIZE; + avctx->block_align = GSM_BLOCK_SIZE; + break; + case AV_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; + } + } + + return 0; +} + +static av_cold int libgsm_encode_close(AVCodecContext *avctx) { + gsm_destroy(avctx->priv_data); + avctx->priv_data = NULL; + return 0; +} + +static int libgsm_encode_frame(AVCodecContext *avctx, AVPacket *avpkt, + const AVFrame *frame, int *got_packet_ptr) +{ + int ret; + gsm_signal *samples = (gsm_signal *)frame->data[0]; + struct gsm_state *state = avctx->priv_data; + + if ((ret = ff_alloc_packet(avpkt, avctx->block_align))) { + av_log(avctx, AV_LOG_ERROR, "Error getting output packet\n"); + return ret; + } + + switch(avctx->codec_id) { + case AV_CODEC_ID_GSM: + gsm_encode(state, samples, avpkt->data); + break; + case AV_CODEC_ID_GSM_MS: + gsm_encode(state, samples, avpkt->data); + gsm_encode(state, samples + GSM_FRAME_SIZE, avpkt->data + 32); + } + + *got_packet_ptr = 1; + return 0; +} + + +AVCodec ff_libgsm_encoder = { + .name = "libgsm", + .long_name = NULL_IF_CONFIG_SMALL("libgsm GSM"), + .type = AVMEDIA_TYPE_AUDIO, + .id = AV_CODEC_ID_GSM, + .init = libgsm_encode_init, + .encode2 = libgsm_encode_frame, + .close = libgsm_encode_close, + .sample_fmts = (const enum AVSampleFormat[]){ AV_SAMPLE_FMT_S16, + AV_SAMPLE_FMT_NONE }, +}; + +AVCodec ff_libgsm_ms_encoder = { + .name = "libgsm_ms", + .long_name = NULL_IF_CONFIG_SMALL("libgsm GSM Microsoft variant"), + .type = AVMEDIA_TYPE_AUDIO, + .id = AV_CODEC_ID_GSM_MS, + .init = libgsm_encode_init, + .encode2 = libgsm_encode_frame, + .close = libgsm_encode_close, + .sample_fmts = (const enum AVSampleFormat[]){ AV_SAMPLE_FMT_S16, + AV_SAMPLE_FMT_NONE }, +}; -- cgit v1.2.3