FFmpeg coverage


Directory: ../../../ffmpeg/
File: src/libavcodec/vb.c
Date: 2024-07-26 21:54:09
Exec Total Coverage
Lines: 124 144 86.1%
Functions: 7 7 100.0%
Branches: 62 84 73.8%

Line Branch Exec Source
1 /*
2 * Beam Software VB decoder
3 * Copyright (c) 2007 Konstantin Shishkov
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 * VB Video decoder
25 */
26
27 #include "libavutil/mem.h"
28 #include "avcodec.h"
29 #include "bytestream.h"
30 #include "codec_internal.h"
31 #include "decode.h"
32
33 enum VBFlags {
34 VB_HAS_GMC = 0x01,
35 VB_HAS_AUDIO = 0x04,
36 VB_HAS_VIDEO = 0x08,
37 VB_HAS_PALETTE = 0x10,
38 VB_HAS_LENGTH = 0x20
39 };
40
41 typedef struct VBDecContext {
42 AVCodecContext *avctx;
43
44 uint8_t *frame, *prev_frame;
45 uint32_t pal[AVPALETTE_COUNT];
46 GetByteContext stream;
47 } VBDecContext;
48
49 static const uint16_t vb_patterns[64] = {
50 0x0660, 0xFF00, 0xCCCC, 0xF000, 0x8888, 0x000F, 0x1111, 0xFEC8,
51 0x8CEF, 0x137F, 0xF731, 0xC800, 0x008C, 0x0013, 0x3100, 0xCC00,
52 0x00CC, 0x0033, 0x3300, 0x0FF0, 0x6666, 0x00F0, 0x0F00, 0x2222,
53 0x4444, 0xF600, 0x8CC8, 0x006F, 0x1331, 0x318C, 0xC813, 0x33CC,
54 0x6600, 0x0CC0, 0x0066, 0x0330, 0xF900, 0xC88C, 0x009F, 0x3113,
55 0x6000, 0x0880, 0x0006, 0x0110, 0xCC88, 0xFC00, 0x00CF, 0x88CC,
56 0x003F, 0x1133, 0x3311, 0xF300, 0x6FF6, 0x0603, 0x08C6, 0x8C63,
57 0xC631, 0x6310, 0xC060, 0x0136, 0x136C, 0x36C8, 0x6C80, 0x324C
58 };
59
60 1 static void vb_decode_palette(VBDecContext *c, int data_size)
61 {
62 int start, size, i;
63
64 1 start = bytestream2_get_byte(&c->stream);
65 1 size = (bytestream2_get_byte(&c->stream) - 1) & 0xFF;
66
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1 if (start + size > 255) {
67 av_log(c->avctx, AV_LOG_ERROR, "Palette change runs beyond entry 256\n");
68 return;
69 }
70
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1 if (size*3+2 > data_size) {
71 av_log(c->avctx, AV_LOG_ERROR, "Palette data runs beyond chunk size\n");
72 return;
73 }
74
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237 for (i = start; i <= start + size; i++)
75 236 c->pal[i] = 0xFFU << 24 | bytestream2_get_be24(&c->stream);
76 }
77
78 73927 static inline int check_pixel(uint8_t *buf, uint8_t *start, uint8_t *end)
79 {
80
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73927 return buf >= start && buf < end;
81 }
82
83 400356 static inline int check_line(uint8_t *buf, uint8_t *start, uint8_t *end)
84 {
85
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400356 return buf >= start && (buf + 4) <= end;
86 }
87
88 40 static int vb_decode_framedata(VBDecContext *c, int offset)
89 {
90 GetByteContext g;
91 uint8_t *prev, *cur;
92 int blk, blocks, t, blk2;
93 40 int blocktypes = 0;
94 int x, y, a, b;
95 int pattype, pattern;
96 40 const int width = c->avctx->width;
97 40 uint8_t *pstart = c->prev_frame;
98 40 uint8_t *pend = c->prev_frame + width*c->avctx->height;
99
100 40 g = c->stream;
101
102 40 prev = c->prev_frame + offset;
103 40 cur = c->frame;
104
105 40 blocks = (c->avctx->width >> 2) * (c->avctx->height >> 2);
106 40 blk2 = 0;
107
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192040 for (blk = 0; blk < blocks; blk++) {
108
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192000 if (!(blk & 3)) {
109
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48000 if (bytestream2_get_bytes_left(&g) < 1) {
110 av_log(c->avctx, AV_LOG_ERROR, "Insufficient data\n");
111 return AVERROR_INVALIDDATA;
112 }
113 48000 blocktypes = bytestream2_get_byte(&g);
114 }
115
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192000 switch (blocktypes & 0xC0) {
116 15137 case 0x00: //skip
117
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75685 for (y = 0; y < 4; y++)
118
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60548 if (check_line(prev + y*width, pstart, pend))
119 60548 memcpy(cur + y*width, prev + y*width, 4);
120 else
121 memset(cur + y*width, 0, 4);
122 15137 break;
123 101466 case 0x40:
124 101466 t = bytestream2_get_byte(&g);
125
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101466 if (!t) { //raw block
126
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16514 if (bytestream2_get_bytes_left(&g) < 16) {
127 av_log(c->avctx, AV_LOG_ERROR, "Insufficient data\n");
128 return AVERROR_INVALIDDATA;
129 }
130
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82570 for (y = 0; y < 4; y++)
131 66056 bytestream2_get_buffer(&g, cur + y * width, 4);
132 } else { // motion compensation
133 84952 x = ((t & 0xF)^8) - 8;
134 84952 y = ((t >> 4) ^8) - 8;
135 84952 t = x + y*width;
136
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137
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339808 if (check_line(prev + t + y*width, pstart, pend))
138 339808 memcpy(cur + y*width, prev + t + y*width, 4);
139 else
140 memset(cur + y*width, 0, 4);
141 }
142 101466 break;
143 12185 case 0x80: // fill
144 12185 t = bytestream2_get_byte(&g);
145
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60925 for (y = 0; y < 4; y++)
146 48740 memset(cur + y*width, t, 4);
147 12185 break;
148 63212 case 0xC0: // pattern fill
149 63212 t = bytestream2_get_byte(&g);
150 63212 pattype = t >> 6;
151
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63212 pattern = vb_patterns[t & 0x3F];
152 switch (pattype) {
153 55330 case 0:
154 55330 a = bytestream2_get_byte(&g);
155 55330 b = bytestream2_get_byte(&g);
156
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276650 for (y = 0; y < 4; y++)
157
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1106600 for (x = 0; x < 4; x++, pattern >>= 1)
158
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885280 cur[x + y*width] = (pattern & 1) ? b : a;
159 55330 break;
160 5188 case 1:
161 5188 pattern = ~pattern;
162 7882 case 2:
163 7882 a = bytestream2_get_byte(&g);
164
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39410 for (y = 0; y < 4; y++)
165
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157640 for (x = 0; x < 4; x++, pattern >>= 1)
166
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126112 if (pattern & 1 && check_pixel(prev + x + y*width, pstart, pend))
167 73927 cur[x + y*width] = prev[x + y*width];
168 else
169 52185 cur[x + y*width] = a;
170 7882 break;
171 case 3:
172 av_log(c->avctx, AV_LOG_ERROR, "Invalid opcode seen @%d\n", blk);
173 return AVERROR_INVALIDDATA;
174 }
175 63212 break;
176 }
177 192000 blocktypes <<= 2;
178 192000 cur += 4;
179 192000 prev += 4;
180 192000 blk2++;
181
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192000 if (blk2 == (width >> 2)) {
182 2400 blk2 = 0;
183 2400 cur += width * 3;
184 2400 prev += width * 3;
185 }
186 }
187 40 return 0;
188 }
189
190 40 static int decode_frame(AVCodecContext *avctx, AVFrame *frame,
191 int *got_frame, AVPacket *avpkt)
192 {
193 40 VBDecContext * const c = avctx->priv_data;
194 uint8_t *outptr, *srcptr;
195 int i, j, ret;
196 int flags;
197 uint32_t size;
198 40 int offset = 0;
199
200
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40 if (avpkt->size < 2)
201 return AVERROR_INVALIDDATA;
202
203 40 bytestream2_init(&c->stream, avpkt->data, avpkt->size);
204
205
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40 if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
206 return ret;
207
208 40 flags = bytestream2_get_le16(&c->stream);
209
210
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40 if (flags & VB_HAS_GMC) {
211 8 i = (int16_t)bytestream2_get_le16(&c->stream);
212 8 j = (int16_t)bytestream2_get_le16(&c->stream);
213
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8 if (FFABS(j) > avctx->height) {
214 av_log(avctx, AV_LOG_ERROR, "GMV out of range\n");
215 return AVERROR_INVALIDDATA;
216 }
217 8 offset = i + j * avctx->width;
218 }
219
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40 if (flags & VB_HAS_VIDEO) {
220 40 size = bytestream2_get_le32(&c->stream);
221
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40 if(size > bytestream2_get_bytes_left(&c->stream)+4 || size<4){
222 av_log(avctx, AV_LOG_ERROR, "Frame size invalid\n");
223 return -1;
224 }
225 40 vb_decode_framedata(c, offset);
226 40 bytestream2_skip(&c->stream, size - 4);
227 }
228
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40 if (flags & VB_HAS_PALETTE) {
229 1 size = bytestream2_get_le32(&c->stream);
230 1 vb_decode_palette(c, size);
231 }
232
233 40 memcpy(frame->data[1], c->pal, AVPALETTE_SIZE);
234 #if FF_API_PALETTE_HAS_CHANGED
235 FF_DISABLE_DEPRECATION_WARNINGS
236 40 frame->palette_has_changed = flags & VB_HAS_PALETTE;
237 FF_ENABLE_DEPRECATION_WARNINGS
238 #endif
239
240 40 outptr = frame->data[0];
241 40 srcptr = c->frame;
242
243
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9640 for (i = 0; i < avctx->height; i++) {
244 9600 memcpy(outptr, srcptr, avctx->width);
245 9600 srcptr += avctx->width;
246 9600 outptr += frame->linesize[0];
247 }
248
249 40 FFSWAP(uint8_t*, c->frame, c->prev_frame);
250
251 40 *got_frame = 1;
252
253 /* always report that the buffer was completely consumed */
254 40 return avpkt->size;
255 }
256
257 3 static av_cold int decode_init(AVCodecContext *avctx)
258 {
259 3 VBDecContext * const c = avctx->priv_data;
260
261 3 c->avctx = avctx;
262 3 avctx->pix_fmt = AV_PIX_FMT_PAL8;
263
264 3 c->frame = av_mallocz(avctx->width * avctx->height);
265 3 c->prev_frame = av_mallocz(avctx->width * avctx->height);
266
267
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3 if (!c->frame || !c->prev_frame)
268 return AVERROR(ENOMEM);
269
270 3 return 0;
271 }
272
273 3 static av_cold int decode_end(AVCodecContext *avctx)
274 {
275 3 VBDecContext *c = avctx->priv_data;
276
277 3 av_freep(&c->frame);
278 3 av_freep(&c->prev_frame);
279
280 3 return 0;
281 }
282
283 const FFCodec ff_vb_decoder = {
284 .p.name = "vb",
285 CODEC_LONG_NAME("Beam Software VB"),
286 .p.type = AVMEDIA_TYPE_VIDEO,
287 .p.id = AV_CODEC_ID_VB,
288 .priv_data_size = sizeof(VBDecContext),
289 .init = decode_init,
290 .close = decode_end,
291 FF_CODEC_DECODE_CB(decode_frame),
292 .p.capabilities = AV_CODEC_CAP_DR1,
293 .caps_internal = FF_CODEC_CAP_INIT_CLEANUP,
294 };
295