/*
* 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 library is free software; you can redistribute it and/or
+ * 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 of the License, or (at your option) any later version.
+ * version 2.1 of the License, or (at your option) any later version.
*
- * This library 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 this library; 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
*/
/**
- * @file libgsm.c
+ * @file
* Interface to libgsm for gsm encoding/decoding
*/
-#include "avcodec.h"
-#include <gsm.h>
+// The idiosyncrasies of GSM-in-WAV are explained at http://kbs.cs.tu-berlin.de/~jutta/toast.html
-// gsm.h miss some essential constants
-#define GSM_BLOCK_SIZE 33
-#define GSM_FRAME_SIZE 160
+#include <gsm/gsm.h>
-static int libgsm_init(AVCodecContext *avctx) {
- if (avctx->channels > 1 || avctx->sample_rate != 8000)
- return -1;
+#include "avcodec.h"
+#include "gsm.h"
- avctx->frame_size = GSM_FRAME_SIZE;
- avctx->block_align = GSM_BLOCK_SIZE;
+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 int libgsm_close(AVCodecContext *avctx) {
+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 < 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;
}
-AVCodec libgsm_encoder = {
- "gsm",
- CODEC_TYPE_AUDIO,
- CODEC_ID_GSM,
- 0,
- libgsm_init,
- libgsm_encode_frame,
- libgsm_close,
+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"),
};
-static int libgsm_decode_frame(AVCodecContext *avctx,
- void *data, int *data_size,
- uint8_t *buf, int buf_size) {
+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;
- if(buf_size < GSM_BLOCK_SIZE) return 0;
+ avctx->sample_fmt = AV_SAMPLE_FMT_S16;
- if(gsm_decode(avctx->priv_data,buf,data)) return -1;
+ s->state = gsm_create();
- *data_size = GSM_FRAME_SIZE*2;
- return GSM_BLOCK_SIZE;
+ 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;
}
-AVCodec libgsm_decoder = {
- "gsm",
- CODEC_TYPE_AUDIO,
- CODEC_ID_GSM,
- 0,
- libgsm_init,
- NULL,
- libgsm_close,
- libgsm_decode_frame,
+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"),
};