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(); return 0;