blob: 878e4cc673cb46b2a4fbcfcd8f5841a26973dc3e
1 | /* |
2 | * Xiph CELT decoder using libcelt |
3 | * Copyright (c) 2011 Nicolas George |
4 | * |
5 | * This file is part of FFmpeg. |
6 | * |
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. |
11 | * |
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. |
16 | * |
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 |
20 | */ |
21 | |
22 | #include <celt/celt.h> |
23 | #include <celt/celt_header.h> |
24 | #include "avcodec.h" |
25 | #include "internal.h" |
26 | #include "libavutil/intreadwrite.h" |
27 | |
28 | struct libcelt_context { |
29 | CELTMode *mode; |
30 | CELTDecoder *dec; |
31 | int discard; |
32 | }; |
33 | |
34 | static int ff_celt_error_to_averror(int err) |
35 | { |
36 | switch (err) { |
37 | case CELT_BAD_ARG: return AVERROR(EINVAL); |
38 | #ifdef CELT_BUFFER_TOO_SMALL |
39 | case CELT_BUFFER_TOO_SMALL: return AVERROR(ENOBUFS); |
40 | #endif |
41 | case CELT_INTERNAL_ERROR: return AVERROR(EFAULT); |
42 | case CELT_CORRUPTED_DATA: return AVERROR_INVALIDDATA; |
43 | case CELT_UNIMPLEMENTED: return AVERROR(ENOSYS); |
44 | #ifdef ENOTRECOVERABLE |
45 | case CELT_INVALID_STATE: return AVERROR(ENOTRECOVERABLE); |
46 | #endif |
47 | case CELT_ALLOC_FAIL: return AVERROR(ENOMEM); |
48 | default: return AVERROR(EINVAL); |
49 | } |
50 | } |
51 | |
52 | static int ff_celt_bitstream_version_hack(CELTMode *mode) |
53 | { |
54 | CELTHeader header = { .version_id = 0 }; |
55 | celt_header_init(&header, mode, 960, 2); |
56 | return header.version_id; |
57 | } |
58 | |
59 | static av_cold int libcelt_dec_init(AVCodecContext *c) |
60 | { |
61 | struct libcelt_context *celt = c->priv_data; |
62 | int err; |
63 | |
64 | if (!c->channels || !c->frame_size || |
65 | c->frame_size > INT_MAX / sizeof(int16_t) / c->channels) |
66 | return AVERROR(EINVAL); |
67 | celt->mode = celt_mode_create(c->sample_rate, c->frame_size, &err); |
68 | if (!celt->mode) |
69 | return ff_celt_error_to_averror(err); |
70 | celt->dec = celt_decoder_create_custom(celt->mode, c->channels, &err); |
71 | if (!celt->dec) { |
72 | celt_mode_destroy(celt->mode); |
73 | return ff_celt_error_to_averror(err); |
74 | } |
75 | if (c->extradata_size >= 4) { |
76 | celt->discard = AV_RL32(c->extradata); |
77 | if (celt->discard < 0 || celt->discard >= c->frame_size) { |
78 | av_log(c, AV_LOG_WARNING, |
79 | "Invalid overlap (%d), ignored.\n", celt->discard); |
80 | celt->discard = 0; |
81 | } |
82 | } |
83 | if (c->extradata_size >= 8) { |
84 | unsigned version = AV_RL32(c->extradata + 4); |
85 | unsigned lib_version = ff_celt_bitstream_version_hack(celt->mode); |
86 | if (version != lib_version) |
87 | av_log(c, AV_LOG_WARNING, |
88 | "CELT bitstream version 0x%x may be " |
89 | "improperly decoded by libcelt for version 0x%x.\n", |
90 | version, lib_version); |
91 | } |
92 | c->sample_fmt = AV_SAMPLE_FMT_S16; |
93 | return 0; |
94 | } |
95 | |
96 | static av_cold int libcelt_dec_close(AVCodecContext *c) |
97 | { |
98 | struct libcelt_context *celt = c->priv_data; |
99 | |
100 | celt_decoder_destroy(celt->dec); |
101 | celt_mode_destroy(celt->mode); |
102 | return 0; |
103 | } |
104 | |
105 | static int libcelt_dec_decode(AVCodecContext *c, void *data, |
106 | int *got_frame_ptr, AVPacket *pkt) |
107 | { |
108 | struct libcelt_context *celt = c->priv_data; |
109 | AVFrame *frame = data; |
110 | int err; |
111 | int16_t *pcm; |
112 | |
113 | frame->nb_samples = c->frame_size; |
114 | if ((err = ff_get_buffer(c, frame, 0)) < 0) |
115 | return err; |
116 | pcm = (int16_t *)frame->data[0]; |
117 | err = celt_decode(celt->dec, pkt->data, pkt->size, pcm, c->frame_size); |
118 | if (err < 0) |
119 | return ff_celt_error_to_averror(err); |
120 | if (celt->discard) { |
121 | frame->nb_samples -= celt->discard; |
122 | memmove(pcm, pcm + celt->discard * c->channels, |
123 | frame->nb_samples * c->channels * sizeof(int16_t)); |
124 | celt->discard = 0; |
125 | } |
126 | *got_frame_ptr = 1; |
127 | return pkt->size; |
128 | } |
129 | |
130 | AVCodec ff_libcelt_decoder = { |
131 | .name = "libcelt", |
132 | .long_name = NULL_IF_CONFIG_SMALL("Xiph CELT decoder using libcelt"), |
133 | .type = AVMEDIA_TYPE_AUDIO, |
134 | .id = AV_CODEC_ID_CELT, |
135 | .priv_data_size = sizeof(struct libcelt_context), |
136 | .init = libcelt_dec_init, |
137 | .close = libcelt_dec_close, |
138 | .decode = libcelt_dec_decode, |
139 | .capabilities = AV_CODEC_CAP_DR1, |
140 | }; |
141 |