2 * Xiph CELT decoder using libcelt
3 * Copyright (c) 2011 Nicolas George
5 * This file is part of FFmpeg.
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
22 #include <celt/celt.h>
23 #include <celt/celt_header.h>
26 #include "libavutil/intreadwrite.h"
28 struct libcelt_context {
35 static int ff_celt_error_to_averror(int err)
38 case CELT_BAD_ARG: return AVERROR(EINVAL);
39 #ifdef CELT_BUFFER_TOO_SMALL
40 case CELT_BUFFER_TOO_SMALL: return AVERROR(ENOBUFS);
42 case CELT_INTERNAL_ERROR: return AVERROR(EFAULT);
43 case CELT_CORRUPTED_DATA: return AVERROR_INVALIDDATA;
44 case CELT_UNIMPLEMENTED: return AVERROR(ENOSYS);
45 #ifdef ENOTRECOVERABLE
46 case CELT_INVALID_STATE: return AVERROR(ENOTRECOVERABLE);
48 case CELT_ALLOC_FAIL: return AVERROR(ENOMEM);
49 default: return AVERROR(EINVAL);
53 static int ff_celt_bitstream_version_hack(CELTMode *mode)
55 CELTHeader header = { .version_id = 0 };
56 celt_header_init(&header, mode, 960, 2);
57 return header.version_id;
60 static av_cold int libcelt_dec_init(AVCodecContext *c)
62 struct libcelt_context *celt = c->priv_data;
65 if (!c->channels || !c->frame_size ||
66 c->frame_size > INT_MAX / sizeof(int16_t) / c->channels)
67 return AVERROR(EINVAL);
68 celt->mode = celt_mode_create(c->sample_rate, c->frame_size, &err);
70 return ff_celt_error_to_averror(err);
71 celt->dec = celt_decoder_create_custom(celt->mode, c->channels, &err);
73 celt_mode_destroy(celt->mode);
74 return ff_celt_error_to_averror(err);
76 if (c->extradata_size >= 4) {
77 celt->discard = AV_RL32(c->extradata);
78 if (celt->discard < 0 || celt->discard >= c->frame_size) {
79 av_log(c, AV_LOG_WARNING,
80 "Invalid overlap (%d), ignored.\n", celt->discard);
84 if (c->extradata_size >= 8) {
85 unsigned version = AV_RL32(c->extradata + 4);
86 unsigned lib_version = ff_celt_bitstream_version_hack(celt->mode);
87 if (version != lib_version)
88 av_log(c, AV_LOG_WARNING,
89 "CELT bitstream version 0x%x may be "
90 "improperly decoded by libcelt for version 0x%x.\n",
91 version, lib_version);
93 c->sample_fmt = AV_SAMPLE_FMT_S16;
94 avcodec_get_frame_defaults(&celt->frame);
95 c->coded_frame = &celt->frame;
99 static av_cold int libcelt_dec_close(AVCodecContext *c)
101 struct libcelt_context *celt = c->priv_data;
103 celt_decoder_destroy(celt->dec);
104 celt_mode_destroy(celt->mode);
108 static int libcelt_dec_decode(AVCodecContext *c, void *frame,
109 int *got_frame_ptr, AVPacket *pkt)
111 struct libcelt_context *celt = c->priv_data;
115 celt->frame.nb_samples = c->frame_size;
116 err = ff_get_buffer(c, &celt->frame);
118 av_log(c, AV_LOG_ERROR, "get_buffer() failed\n");
121 pcm = (int16_t *)celt->frame.data[0];
122 err = celt_decode(celt->dec, pkt->data, pkt->size, pcm, c->frame_size);
124 return ff_celt_error_to_averror(err);
126 celt->frame.nb_samples -= celt->discard;
127 memmove(pcm, pcm + celt->discard * c->channels,
128 celt->frame.nb_samples * c->channels * sizeof(int16_t));
132 *(AVFrame *)frame = celt->frame;
136 AVCodec ff_libcelt_decoder = {
138 .type = AVMEDIA_TYPE_AUDIO,
139 .id = AV_CODEC_ID_CELT,
140 .priv_data_size = sizeof(struct libcelt_context),
141 .init = libcelt_dec_init,
142 .close = libcelt_dec_close,
143 .decode = libcelt_dec_decode,
144 .capabilities = CODEC_CAP_DR1,
145 .long_name = NULL_IF_CONFIG_SMALL("Xiph CELT decoder using libcelt"),