FFmpeg coverage

Directory: ../../../ffmpeg/
File: src/libavcodec/8svx.c
Date: 2026-01-23 19:11:46
Exec Total Coverage
Lines: 51 68 75.0%
Functions: 4 4 100.0%
Branches: 19 35 54.3%
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1 /*
2 * Copyright (C) 2008 Jaikrishnan Menon
3 * Copyright (C) 2011 Stefano Sabatini
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 /**
23 * @file
24 * 8svx audio decoder
25 * @author Jaikrishnan Menon
26 *
27 * supports: fibonacci delta encoding
28 * : exponential encoding
29 *
30 * For more information about the 8SVX format:
31 * http://netghost.narod.ru/gff/vendspec/iff/iff.txt
32 * http://sox.sourceforge.net/AudioFormats-11.html
33 * http://aminet.net/package/mus/misc/wavepak
34 * http://amigan.1emu.net/reg/8SVX.txt
35 *
36 * Samples can be found here:
37 * http://aminet.net/mods/smpl/
38 */
39
40 #include "config_components.h"
41
42 #include "libavutil/avassert.h"
43 #include "libavutil/mem.h"
44 #include "avcodec.h"
45 #include "codec_internal.h"
46 #include "decode.h"
47 #include "libavutil/common.h"
48
49 /** decoder context */
50 typedef struct EightSvxContext {
51 uint8_t fib_acc[2];
52 const int8_t *table;
53
54 /* buffer used to store the whole first packet.
55 data is only sent as one large packet */
56 uint8_t *data[2];
57 int data_size;
58 int data_idx;
59 } EightSvxContext;
60
61 static const int8_t fibonacci[16] = { -34, -21, -13, -8, -5, -3, -2, -1, 0, 1, 2, 3, 5, 8, 13, 21 };
62 static const int8_t exponential[16] = { -128, -64, -32, -16, -8, -4, -2, -1, 0, 1, 2, 4, 8, 16, 32, 64 };
63
64 #define MAX_FRAME_SIZE 2048
65
66 /**
67 * Delta decode the compressed values in src, and put the resulting
68 * decoded samples in dst.
69 *
70 * @param[in,out] state starting value. it is saved for use in the next call.
71 * @param table delta sequence table
72 */
73 40 static void delta_decode(uint8_t *dst, const uint8_t *src, int src_size,
74 uint8_t *state, const int8_t *table)
75 {
76 40 uint8_t val = *state;
77
78
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 80168 while (src_size--) {
79 80128 uint8_t d = *src++;
80 80128 val = av_clip_uint8(val + table[d & 0xF]);
81 80128 *dst++ = val;
82 80128 val = av_clip_uint8(val + table[d >> 4]);
83 80128 *dst++ = val;
84 }
85
86 40 *state = val;
87 40 }
88
89 /** decode a frame */
90 40 static int eightsvx_decode_frame(AVCodecContext *avctx, AVFrame *frame,
91 int *got_frame_ptr, AVPacket *avpkt)
92 {
93 40 EightSvxContext *esc = avctx->priv_data;
94 40 int channels = avctx->ch_layout.nb_channels;
95 int buf_size;
96 int ch, ret;
97 40 int hdr_size = 2;
98
99 /* decode and interleave the first packet */
100
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 40 if (!esc->data[0] && avpkt) {
101 1 int chan_size = avpkt->size / channels - hdr_size;
102
103
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 1 if (avpkt->size % channels) {
104 ✗ av_log(avctx, AV_LOG_WARNING, "Packet with odd size, ignoring last byte\n");
105 }
106
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 1 if (avpkt->size < (hdr_size + 1) * channels) {
107 ✗ av_log(avctx, AV_LOG_ERROR, "packet size is too small\n");
108 ✗ return AVERROR_INVALIDDATA;
109 }
110
111 1 esc->fib_acc[0] = avpkt->data[1] + 128;
112
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 1 if (channels == 2)
113 ✗ esc->fib_acc[1] = avpkt->data[2+chan_size+1] + 128;
114
115 1 esc->data_idx = 0;
116 1 esc->data_size = chan_size;
117
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 1 if (!(esc->data[0] = av_malloc(chan_size)))
118 ✗ return AVERROR(ENOMEM);
119
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 1 if (channels == 2) {
120 ✗ if (!(esc->data[1] = av_malloc(chan_size))) {
121 ✗ av_freep(&esc->data[0]);
122 ✗ return AVERROR(ENOMEM);
123 }
124 }
125 1 memcpy(esc->data[0], &avpkt->data[hdr_size], chan_size);
126
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 1 if (channels == 2)
127 ✗ memcpy(esc->data[1], &avpkt->data[2*hdr_size+chan_size], chan_size);
128 }
129
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 40 if (!esc->data[0]) {
130 ✗ av_log(avctx, AV_LOG_ERROR, "unexpected empty packet\n");
131 ✗ return AVERROR_INVALIDDATA;
132 }
133
134 /* decode next piece of data from the buffer */
135 40 buf_size = FFMIN(MAX_FRAME_SIZE, esc->data_size - esc->data_idx);
136
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 40 if (buf_size <= 0) {
137 ✗ *got_frame_ptr = 0;
138 ✗ return avpkt->size;
139 }
140
141 /* get output buffer */
142 40 frame->nb_samples = buf_size * 2;
143
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 40 if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
144 ✗ return ret;
145
146
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 80 for (ch = 0; ch < channels; ch++) {
147 40 delta_decode(frame->data[ch], &esc->data[ch][esc->data_idx],
148 buf_size, &esc->fib_acc[ch], esc->table);
149 }
150
151 40 esc->data_idx += buf_size;
152
153 40 *got_frame_ptr = 1;
154
155 40 return ((avctx->frame_num == 0) * hdr_size + buf_size) * channels;
156 }
157
158 2 static av_cold int eightsvx_decode_init(AVCodecContext *avctx)
159 {
160 2 EightSvxContext *esc = avctx->priv_data;
161
162
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 2 if (avctx->ch_layout.nb_channels < 1 || avctx->ch_layout.nb_channels > 2) {
163 ✗ av_log(avctx, AV_LOG_ERROR, "8SVX does not support more than 2 channels\n");
164 ✗ return AVERROR_INVALIDDATA;
165 }
166
167
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 2 switch (avctx->codec->id) {
168 2 case AV_CODEC_ID_8SVX_FIB: esc->table = fibonacci; break;
169 ✗ case AV_CODEC_ID_8SVX_EXP: esc->table = exponential; break;
170 2 default:
171 av_assert1(0);
172 }
173 2 avctx->sample_fmt = AV_SAMPLE_FMT_U8P;
174
175 2 return 0;
176 }
177
178 2 static av_cold int eightsvx_decode_close(AVCodecContext *avctx)
179 {
180 2 EightSvxContext *esc = avctx->priv_data;
181
182 2 av_freep(&esc->data[0]);
183 2 av_freep(&esc->data[1]);
184 2 esc->data_size = 0;
185 2 esc->data_idx = 0;
186
187 2 return 0;
188 }
189
190 #if CONFIG_EIGHTSVX_FIB_DECODER
191 const FFCodec ff_eightsvx_fib_decoder = {
192 .p.name = "8svx_fib",
193 CODEC_LONG_NAME("8SVX fibonacci"),
194 .p.type = AVMEDIA_TYPE_AUDIO,
195 .p.id = AV_CODEC_ID_8SVX_FIB,
196 .priv_data_size = sizeof (EightSvxContext),
197 .init = eightsvx_decode_init,
198 FF_CODEC_DECODE_CB(eightsvx_decode_frame),
199 .close = eightsvx_decode_close,
200 .p.capabilities = AV_CODEC_CAP_DR1,
201 CODEC_SAMPLEFMTS(AV_SAMPLE_FMT_U8P),
202 };
203 #endif
204 #if CONFIG_EIGHTSVX_EXP_DECODER
205 const FFCodec ff_eightsvx_exp_decoder = {
206 .p.name = "8svx_exp",
207 CODEC_LONG_NAME("8SVX exponential"),
208 .p.type = AVMEDIA_TYPE_AUDIO,
209 .p.id = AV_CODEC_ID_8SVX_EXP,
210 .priv_data_size = sizeof (EightSvxContext),
211 .init = eightsvx_decode_init,
212 FF_CODEC_DECODE_CB(eightsvx_decode_frame),
213 .close = eightsvx_decode_close,
214 .p.capabilities = AV_CODEC_CAP_DR1,
215 CODEC_SAMPLEFMTS(AV_SAMPLE_FMT_U8P),
216 };
217 #endif
218