1 /*
2 * Packed Animation File audio decoder
3 * Copyright (c) 2012 Paul B Mahol
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 "libavutil/intreadwrite.h"
23
24 #include "avcodec.h"
25 #include "internal.h"
26 #include "mathops.h"
27 #include "paf.h"
28
paf_audio_init(AVCodecContext * avctx)29 static av_cold int paf_audio_init(AVCodecContext *avctx)
30 {
31 if (avctx->channels != 2) {
32 av_log(avctx, AV_LOG_ERROR, "invalid number of channels\n");
33 return AVERROR_INVALIDDATA;
34 }
35
36 avctx->channel_layout = AV_CH_LAYOUT_STEREO;
37 avctx->sample_fmt = AV_SAMPLE_FMT_S16;
38
39 return 0;
40 }
41
paf_audio_decode(AVCodecContext * avctx,void * data,int * got_frame,AVPacket * pkt)42 static int paf_audio_decode(AVCodecContext *avctx, void *data,
43 int *got_frame, AVPacket *pkt)
44 {
45 AVFrame *frame = data;
46 int16_t *output_samples;
47 const uint8_t *src = pkt->data;
48 int frames, ret, i, j;
49 int16_t cb[256];
50
51 frames = pkt->size / PAF_SOUND_FRAME_SIZE;
52 if (frames < 1)
53 return AVERROR_INVALIDDATA;
54
55 frame->nb_samples = PAF_SOUND_SAMPLES * frames;
56 if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
57 return ret;
58
59 output_samples = (int16_t *)frame->data[0];
60 // codebook of 256 16-bit samples and 8-bit indices to it
61 for (j = 0; j < frames; j++) {
62 for (i = 0; i < 256; i++)
63 cb[i] = sign_extend(AV_RL16(src + i * 2), 16);
64 src += 256 * 2;
65 // always 2 channels
66 for (i = 0; i < PAF_SOUND_SAMPLES * 2; i++)
67 *output_samples++ = cb[*src++];
68 }
69 *got_frame = 1;
70
71 return pkt->size;
72 }
73
74 AVCodec ff_paf_audio_decoder = {
75 .name = "paf_audio",
76 .long_name = NULL_IF_CONFIG_SMALL("Amazing Studio Packed Animation File Audio"),
77 .type = AVMEDIA_TYPE_AUDIO,
78 .id = AV_CODEC_ID_PAF_AUDIO,
79 .init = paf_audio_init,
80 .decode = paf_audio_decode,
81 .capabilities = AV_CODEC_CAP_DR1,
82 .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE,
83 };
84