ffmpeg/libavcodec/libspeexdec.c

   1 /*
   2  * Copyright (C) 2008 David Conrad
   3  *
   4  * This file is part of FFmpeg.
   5  *
   6  * FFmpeg is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2.1 of the License, or (at your option) any later version.
  10  *
  11  * FFmpeg is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with FFmpeg; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  19  */
  20
  21 #include <speex/speex.h>
  22 #include <speex/speex_header.h>
  23 #include <speex/speex_stereo.h>
  24 #include <speex/speex_callbacks.h>
  25
  26 #include "libavutil/channel_layout.h"
  27 #include "libavutil/common.h"
  28 #include "avcodec.h"
  29 #include "internal.h"
  30
  31 typedef struct {
  32     SpeexBits bits;
  33     SpeexStereoState stereo;
  34     void *dec_state;
  35     int frame_size;
  36     int pktsize;
  37 } LibSpeexContext;
  38
  39
  40 static av_cold int libspeex_decode_init(AVCodecContext *avctx)
  41 {
  42     LibSpeexContext *s = avctx->priv_data;
  43     const SpeexMode *mode;
  44     SpeexHeader *header = NULL;
  45     int spx_mode;
  46
  47     if (avctx->extradata && avctx->extradata_size >= 80) {
  48         header = speex_packet_to_header(avctx->extradata,
  49                                         avctx->extradata_size);
  50         if (!header)
  51             av_log(avctx, AV_LOG_WARNING, "Invalid Speex header\n");
  52     }
  53     if (avctx->codec_tag == MKTAG('S', 'P', 'X', 'N')) {
  54         int quality;
  55         if (!avctx->extradata || avctx->extradata && avctx->extradata_size < 47) {
  56             av_log(avctx, AV_LOG_ERROR, "Missing or invalid extradata.\n");
  57             return AVERROR_INVALIDDATA;
  58         }
  59
  60         quality = avctx->extradata[37];
  61         if (quality > 10) {
  62             av_log(avctx, AV_LOG_ERROR, "Unsupported quality mode %d.\n", quality);
  63             return AVERROR_PATCHWELCOME;
  64         }
  65
  66         s->pktsize = ((const int[]){5,10,15,20,20,28,28,38,38,46,62})[quality];
  67
  68         spx_mode           = 0;
  69     } else if (header) {
  70         avctx->sample_rate = header->rate;
  71         avctx->channels    = header->nb_channels;
  72         spx_mode           = header->mode;
  73         speex_header_free(header);
  74     } else {
  75         switch (avctx->sample_rate) {
  76         case 8000:  spx_mode = 0; break;
  77         case 16000: spx_mode = 1; break;
  78         case 32000: spx_mode = 2; break;
  79         default:
  80             /* libspeex can handle any mode if initialized as ultra-wideband */
  81             av_log(avctx, AV_LOG_WARNING, "Invalid sample rate: %d\n"
  82                                           "Decoding as 32kHz ultra-wideband\n",
  83                                           avctx->sample_rate);
  84             spx_mode = 2;
  85         }
  86     }
  87
  88     mode = speex_lib_get_mode(spx_mode);
  89     if (!mode) {
  90         av_log(avctx, AV_LOG_ERROR, "Unknown Speex mode %d", spx_mode);
  91         return AVERROR_INVALIDDATA;
  92     }
  93     s->frame_size      =  160 << spx_mode;
  94     if (!avctx->sample_rate)
  95         avctx->sample_rate = 8000 << spx_mode;
  96
  97     if (avctx->channels < 1 || avctx->channels > 2) {
  98         /* libspeex can handle mono or stereo if initialized as stereo */
  99         av_log(avctx, AV_LOG_ERROR, "Invalid channel count: %d.\n"
 100                                     "Decoding as stereo.\n", avctx->channels);
 101         avctx->channels = 2;
 102     }
 103     avctx->channel_layout = avctx->channels == 2 ? AV_CH_LAYOUT_STEREO :
 104                                                    AV_CH_LAYOUT_MONO;
 105
 106     speex_bits_init(&s->bits);
 107     s->dec_state = speex_decoder_init(mode);
 108     if (!s->dec_state) {
 109         av_log(avctx, AV_LOG_ERROR, "Error initializing libspeex decoder.\n");
 110         return -1;
 111     }
 112
 113     if (avctx->channels == 2) {
 114         SpeexCallback callback;
 115         callback.callback_id = SPEEX_INBAND_STEREO;
 116         callback.func = speex_std_stereo_request_handler;
 117         callback.data = &s->stereo;
 118         s->stereo = (SpeexStereoState)SPEEX_STEREO_STATE_INIT;
 119         speex_decoder_ctl(s->dec_state, SPEEX_SET_HANDLER, &callback);
 120     }
 121
 122     return 0;
 123 }
 124
 125 static int libspeex_decode_frame(AVCodecContext *avctx, void *data,
 126                                  int *got_frame_ptr, AVPacket *avpkt)
 127 {
 128     uint8_t *buf = avpkt->data;
 129     int buf_size = avpkt->size;
 130     LibSpeexContext *s = avctx->priv_data;
 131     AVFrame *frame     = data;
 132     int16_t *output;
 133     int ret, consumed = 0;
 134     avctx->sample_fmt = AV_SAMPLE_FMT_S16;
 135
 136     /* get output buffer */
 137     frame->nb_samples = s->frame_size;
 138     if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
 139         return ret;
 140     output = (int16_t *)frame->data[0];
 141
 142     /* if there is not enough data left for the smallest possible frame or the
 143        next 5 bits are a terminator code, reset the libspeex buffer using the
 144        current packet, otherwise ignore the current packet and keep decoding
 145        frames from the libspeex buffer. */
 146     if (speex_bits_remaining(&s->bits) < 5 ||
 147         speex_bits_peek_unsigned(&s->bits, 5) == 0xF) {
 148         /* check for flush packet */
 149         if (!buf || !buf_size) {
 150             *got_frame_ptr = 0;
 151             return buf_size;
 152         }
 153         if (s->pktsize && buf_size == 62)
 154             buf_size = s->pktsize;
 155         /* set new buffer */
 156         speex_bits_read_from(&s->bits, buf, buf_size);
 157         consumed = avpkt->size;
 158     }
 159
 160     /* decode a single frame */
 161     ret = speex_decode_int(s->dec_state, &s->bits, output);
 162     if (ret <= -2) {
 163         av_log(avctx, AV_LOG_ERROR, "Error decoding Speex frame.\n");
 164         return AVERROR_INVALIDDATA;
 165     }
 166     if (avctx->channels == 2)
 167         speex_decode_stereo_int(output, s->frame_size, &s->stereo);
 168
 169     *got_frame_ptr = 1;
 170
 171     if (!avctx->bit_rate)
 172         speex_decoder_ctl(s->dec_state, SPEEX_GET_BITRATE, &avctx->bit_rate);
 173     return consumed;
 174 }
 175
 176 static av_cold int libspeex_decode_close(AVCodecContext *avctx)
 177 {
 178     LibSpeexContext *s = avctx->priv_data;
 179
 180     speex_bits_destroy(&s->bits);
 181     speex_decoder_destroy(s->dec_state);
 182
 183     return 0;
 184 }
 185
 186 static av_cold void libspeex_decode_flush(AVCodecContext *avctx)
 187 {
 188     LibSpeexContext *s = avctx->priv_data;
 189     speex_bits_reset(&s->bits);
 190 }
 191
 192 AVCodec ff_libspeex_decoder = {
 193     .name           = "libspeex",
 194     .long_name      = NULL_IF_CONFIG_SMALL("libspeex Speex"),
 195     .type           = AVMEDIA_TYPE_AUDIO,
 196     .id             = AV_CODEC_ID_SPEEX,
 197     .priv_data_size = sizeof(LibSpeexContext),
 198     .init           = libspeex_decode_init,
 199     .close          = libspeex_decode_close,
 200     .decode         = libspeex_decode_frame,
 201     .flush          = libspeex_decode_flush,
 202     .capabilities   = CODEC_CAP_SUBFRAMES | CODEC_CAP_DELAY | CODEC_CAP_DR1,
 203 };