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libspeexdec.c
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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 
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;
37 
38 
40 {
41  LibSpeexContext *s = avctx->priv_data;
42  const SpeexMode *mode;
43  SpeexHeader *header = NULL;
44  int spx_mode;
45 
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  if (!avctx->extradata || avctx->extradata && avctx->extradata_size < 47) {
55  av_log(avctx, AV_LOG_ERROR, "Missing or invalid extradata.\n");
56  return AVERROR_INVALIDDATA;
57  }
58  if (avctx->extradata[37] != 10) {
59  av_log(avctx, AV_LOG_ERROR, "Unsupported quality mode.\n");
60  return AVERROR_PATCHWELCOME;
61  }
62  spx_mode = 0;
63  } else if (header) {
64  avctx->sample_rate = header->rate;
65  avctx->channels = header->nb_channels;
66  spx_mode = header->mode;
67  speex_header_free(header);
68  } else {
69  switch (avctx->sample_rate) {
70  case 8000: spx_mode = 0; break;
71  case 16000: spx_mode = 1; break;
72  case 32000: spx_mode = 2; break;
73  default:
74  /* libspeex can handle any mode if initialized as ultra-wideband */
75  av_log(avctx, AV_LOG_WARNING, "Invalid sample rate: %d\n"
76  "Decoding as 32kHz ultra-wideband\n",
77  avctx->sample_rate);
78  spx_mode = 2;
79  }
80  }
81 
82  mode = speex_lib_get_mode(spx_mode);
83  if (!mode) {
84  av_log(avctx, AV_LOG_ERROR, "Unknown Speex mode %d", spx_mode);
85  return AVERROR_INVALIDDATA;
86  }
87  s->frame_size = 160 << spx_mode;
88  if (!avctx->sample_rate)
89  avctx->sample_rate = 8000 << spx_mode;
90 
91  if (avctx->channels < 1 || avctx->channels > 2) {
92  /* libspeex can handle mono or stereo if initialized as stereo */
93  av_log(avctx, AV_LOG_ERROR, "Invalid channel count: %d.\n"
94  "Decoding as stereo.\n", avctx->channels);
95  avctx->channels = 2;
96  }
97  avctx->channel_layout = avctx->channels == 2 ? AV_CH_LAYOUT_STEREO :
99 
100  speex_bits_init(&s->bits);
101  s->dec_state = speex_decoder_init(mode);
102  if (!s->dec_state) {
103  av_log(avctx, AV_LOG_ERROR, "Error initializing libspeex decoder.\n");
104  return -1;
105  }
106 
107  if (avctx->channels == 2) {
108  SpeexCallback callback;
109  callback.callback_id = SPEEX_INBAND_STEREO;
110  callback.func = speex_std_stereo_request_handler;
111  callback.data = &s->stereo;
112  s->stereo = (SpeexStereoState)SPEEX_STEREO_STATE_INIT;
113  speex_decoder_ctl(s->dec_state, SPEEX_SET_HANDLER, &callback);
114  }
115 
116  return 0;
117 }
118 
119 static int libspeex_decode_frame(AVCodecContext *avctx, void *data,
120  int *got_frame_ptr, AVPacket *avpkt)
121 {
122  uint8_t *buf = avpkt->data;
123  int buf_size = avpkt->size;
124  LibSpeexContext *s = avctx->priv_data;
125  AVFrame *frame = data;
126  int16_t *output;
127  int ret, consumed = 0;
128  avctx->sample_fmt = AV_SAMPLE_FMT_S16;
129 
130  /* get output buffer */
131  frame->nb_samples = s->frame_size;
132  if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
133  return ret;
134  output = (int16_t *)frame->data[0];
135 
136  /* if there is not enough data left for the smallest possible frame or the
137  next 5 bits are a terminator code, reset the libspeex buffer using the
138  current packet, otherwise ignore the current packet and keep decoding
139  frames from the libspeex buffer. */
140  if (speex_bits_remaining(&s->bits) < 5 ||
141  speex_bits_peek_unsigned(&s->bits, 5) == 0xF) {
142  /* check for flush packet */
143  if (!buf || !buf_size) {
144  *got_frame_ptr = 0;
145  return buf_size;
146  }
147  /* set new buffer */
148  speex_bits_read_from(&s->bits, buf, buf_size);
149  consumed = buf_size;
150  }
151 
152  /* decode a single frame */
153  ret = speex_decode_int(s->dec_state, &s->bits, output);
154  if (ret <= -2) {
155  av_log(avctx, AV_LOG_ERROR, "Error decoding Speex frame.\n");
156  return AVERROR_INVALIDDATA;
157  }
158  if (avctx->channels == 2)
159  speex_decode_stereo_int(output, s->frame_size, &s->stereo);
160 
161  *got_frame_ptr = 1;
162 
163  if (!avctx->bit_rate)
164  speex_decoder_ctl(s->dec_state, SPEEX_GET_BITRATE, &avctx->bit_rate);
165  return consumed;
166 }
167 
169 {
170  LibSpeexContext *s = avctx->priv_data;
171 
172  speex_bits_destroy(&s->bits);
173  speex_decoder_destroy(s->dec_state);
174 
175  return 0;
176 }
177 
179 {
180  LibSpeexContext *s = avctx->priv_data;
181  speex_bits_reset(&s->bits);
182 }
183 
185  .name = "libspeex",
186  .long_name = NULL_IF_CONFIG_SMALL("libspeex Speex"),
187  .type = AVMEDIA_TYPE_AUDIO,
188  .id = AV_CODEC_ID_SPEEX,
189  .priv_data_size = sizeof(LibSpeexContext),
195 };