3 * Copyright (c) 2005 Konstantin Shishkov
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
25 * Westwood SNDx codecs.
27 * Reference documents about VQA format and its audio codecs
29 * http://www.multimedia.cx
32 static const char ws_adpcm_2bit[] = { -2, -1, 0, 1};
33 static const char ws_adpcm_4bit[] = {
34 -9, -8, -6, -5, -4, -3, -2, -1,
35 0, 1, 2, 3, 4, 5, 6, 8 };
37 #define CLIP8(a) if(a>127)a=127;if(a<-128)a=-128;
39 static av_cold int ws_snd_decode_init(AVCodecContext * avctx)
41 // WSSNDContext *c = avctx->priv_data;
43 avctx->sample_fmt = SAMPLE_FMT_S16;
47 static int ws_snd_decode_frame(AVCodecContext *avctx,
48 void *data, int *data_size,
49 const uint8_t *buf, int buf_size)
51 // WSSNDContext *c = avctx->priv_data;
53 int in_size, out_size;
56 short *samples = data;
61 out_size = AV_RL16(&buf[0]);
62 *data_size = out_size * 2;
63 in_size = AV_RL16(&buf[2]);
66 if (out_size > *data_size) {
67 av_log(avctx, AV_LOG_ERROR, "Frame is too large to fit in buffer\n");
70 if (in_size > buf_size) {
71 av_log(avctx, AV_LOG_ERROR, "Frame data is larger than input buffer\n");
74 if (in_size == out_size) {
75 for (i = 0; i < out_size; i++)
76 *samples++ = (*buf++ - 0x80) << 8;
80 while (out_size > 0) {
84 count = (*buf) & 0x3F;
87 case 0: /* ADPCM 2-bit */
88 for (count++; count > 0; count--) {
90 sample += ws_adpcm_2bit[code & 0x3];
92 *samples++ = sample << 8;
93 sample += ws_adpcm_2bit[(code >> 2) & 0x3];
95 *samples++ = sample << 8;
96 sample += ws_adpcm_2bit[(code >> 4) & 0x3];
98 *samples++ = sample << 8;
99 sample += ws_adpcm_2bit[(code >> 6) & 0x3];
101 *samples++ = sample << 8;
105 case 1: /* ADPCM 4-bit */
106 for (count++; count > 0; count--) {
108 sample += ws_adpcm_4bit[code & 0xF];
110 *samples++ = sample << 8;
111 sample += ws_adpcm_4bit[code >> 4];
113 *samples++ = sample << 8;
117 case 2: /* no compression */
118 if (count & 0x20) { /* big delta */
123 *samples++ = sample << 8;
126 for (count++; count > 0; count--) {
127 *samples++ = (*buf++ - 0x80) << 8;
130 sample = buf[-1] - 0x80;
134 for(count++; count > 0; count--) {
135 *samples++ = sample << 8;
144 AVCodec ws_snd1_decoder = {
147 CODEC_ID_WESTWOOD_SND1,
153 .long_name = NULL_IF_CONFIG_SMALL("Westwood Audio (SND1)"),