FFmpeg coverage


Directory: ../../../ffmpeg/
File: src/libavcodec/smc.c
Date: 2022-11-28 23:49:43
Exec Total Coverage
Lines: 173 219 79.0%
Branches: 102 151 67.5%

Line Branch Exec Source
1 /*
2 * Quicktime Graphics (SMC) Video Decoder
3 * Copyright (C) 2003 The FFmpeg project
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 * QT SMC Video Decoder by Mike Melanson (melanson@pcisys.net)
25 * For more information about the SMC format, visit:
26 * http://www.pcisys.net/~melanson/codecs/
27 *
28 * The SMC decoder outputs PAL8 colorspace data.
29 */
30
31 #include <string.h>
32
33 #include "avcodec.h"
34 #include "bytestream.h"
35 #include "codec_internal.h"
36 #include "decode.h"
37
38 #define CPAIR 2
39 #define CQUAD 4
40 #define COCTET 8
41
42 #define COLORS_PER_TABLE 256
43
44 typedef struct SmcContext {
45
46 AVCodecContext *avctx;
47 AVFrame *frame;
48
49 /* SMC color tables */
50 uint8_t color_pairs[COLORS_PER_TABLE * CPAIR];
51 uint8_t color_quads[COLORS_PER_TABLE * CQUAD];
52 uint8_t color_octets[COLORS_PER_TABLE * COCTET];
53
54 uint32_t pal[256];
55 } SmcContext;
56
57 #define GET_BLOCK_COUNT() \
58 (opcode & 0x10) ? (1 + bytestream2_get_byte(gb)) : 1 + (opcode & 0x0F);
59
60 #define ADVANCE_BLOCK() \
61 { \
62 pixel_ptr += 4; \
63 if (pixel_ptr >= width) \
64 { \
65 pixel_ptr = 0; \
66 row_ptr += stride * 4; \
67 } \
68 total_blocks--; \
69 if (total_blocks < !!n_blocks) \
70 { \
71 av_log(s->avctx, AV_LOG_ERROR, "block counter just went negative (this should not happen)\n"); \
72 return AVERROR_INVALIDDATA; \
73 } \
74 }
75
76 120 static int smc_decode_stream(SmcContext *s, GetByteContext *gb)
77 {
78 120 int width = s->avctx->width;
79 120 int height = s->avctx->height;
80 120 int stride = s->frame->linesize[0];
81 int i;
82 int chunk_size;
83 120 int buf_size = bytestream2_size(gb);
84 uint8_t opcode;
85 int n_blocks;
86 unsigned int color_flags;
87 unsigned int color_flags_a;
88 unsigned int color_flags_b;
89 unsigned int flag_mask;
90
91 120 uint8_t * const pixels = s->frame->data[0];
92
93 120 int image_size = height * s->frame->linesize[0];
94 120 int row_ptr = 0;
95 120 int pixel_ptr = 0;
96 int pixel_x, pixel_y;
97 120 int row_inc = stride - 4;
98 int block_ptr;
99 int prev_block_ptr;
100 int prev_block_ptr1, prev_block_ptr2;
101 int prev_block_flag;
102 int total_blocks;
103 int color_table_index; /* indexes to color pair, quad, or octet tables */
104 int pixel;
105
106 120 int color_pair_index = 0;
107 120 int color_quad_index = 0;
108 120 int color_octet_index = 0;
109
110 /* make the palette available */
111 120 memcpy(s->frame->data[1], s->pal, AVPALETTE_SIZE);
112
113 120 bytestream2_skip(gb, 1);
114 120 chunk_size = bytestream2_get_be24(gb);
115
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 120 times.
120 if (chunk_size != buf_size)
116 av_log(s->avctx, AV_LOG_WARNING, "MOV chunk size != encoded chunk size (%d != %d); using MOV chunk size\n",
117 chunk_size, buf_size);
118
119 120 chunk_size = buf_size;
120 120 total_blocks = ((s->avctx->width + 3) / 4) * ((s->avctx->height + 3) / 4);
121
122 /* traverse through the blocks */
123
2/2
✓ Branch 0 taken 130697 times.
✓ Branch 1 taken 120 times.
130817 while (total_blocks) {
124 /* sanity checks */
125 /* make sure the row pointer hasn't gone wild */
126
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 130697 times.
130697 if (row_ptr >= image_size) {
127 av_log(s->avctx, AV_LOG_ERROR, "just went out of bounds (row ptr = %d, height = %d)\n",
128 row_ptr, image_size);
129 return AVERROR_INVALIDDATA;
130 }
131
1/2
✗ Branch 1 not taken.
✓ Branch 2 taken 130697 times.
130697 if (bytestream2_get_bytes_left(gb) < 1) {
132 av_log(s->avctx, AV_LOG_ERROR, "input too small\n");
133 return AVERROR_INVALIDDATA;
134 }
135
136 130697 opcode = bytestream2_get_byteu(gb);
137
7/9
✓ Branch 0 taken 28630 times.
✓ Branch 1 taken 1068 times.
✗ Branch 2 not taken.
✓ Branch 3 taken 11688 times.
✓ Branch 4 taken 17912 times.
✓ Branch 5 taken 35882 times.
✓ Branch 6 taken 33474 times.
✓ Branch 7 taken 2043 times.
✗ Branch 8 not taken.
130697 switch (opcode & 0xF0) {
138 /* skip n blocks */
139 28630 case 0x00:
140 case 0x10:
141
2/2
✓ Branch 0 taken 11959 times.
✓ Branch 1 taken 16671 times.
28630 n_blocks = GET_BLOCK_COUNT();
142
2/2
✓ Branch 0 taken 418385 times.
✓ Branch 1 taken 28630 times.
447015 while (n_blocks--) {
143
3/4
✓ Branch 0 taken 6375 times.
✓ Branch 1 taken 412010 times.
✗ Branch 2 not taken.
✓ Branch 3 taken 418385 times.
418385 ADVANCE_BLOCK();
144 }
145 28630 break;
146
147 /* repeat last block n times */
148 1068 case 0x20:
149 case 0x30:
150
2/2
✓ Branch 0 taken 11 times.
✓ Branch 1 taken 1057 times.
1068 n_blocks = GET_BLOCK_COUNT();
151
152 /* sanity check */
153
1/4
✗ Branch 0 not taken.
✓ Branch 1 taken 1068 times.
✗ Branch 2 not taken.
✗ Branch 3 not taken.
1068 if ((row_ptr == 0) && (pixel_ptr == 0)) {
154 av_log(s->avctx, AV_LOG_ERROR, "encountered repeat block opcode (%02X) but no blocks rendered yet\n",
155 opcode & 0xF0);
156 return AVERROR_INVALIDDATA;
157 }
158
159 /* figure out where the previous block started */
160
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 1068 times.
1068 if (pixel_ptr == 0)
161 prev_block_ptr1 =
162 (row_ptr - s->avctx->width * 4) + s->avctx->width - 4;
163 else
164 1068 prev_block_ptr1 = row_ptr + pixel_ptr - 4;
165
166
2/2
✓ Branch 0 taken 2325 times.
✓ Branch 1 taken 1068 times.
3393 while (n_blocks--) {
167 2325 block_ptr = row_ptr + pixel_ptr;
168 2325 prev_block_ptr = prev_block_ptr1;
169
2/2
✓ Branch 0 taken 9300 times.
✓ Branch 1 taken 2325 times.
11625 for (pixel_y = 0; pixel_y < 4; pixel_y++) {
170
2/2
✓ Branch 0 taken 37200 times.
✓ Branch 1 taken 9300 times.
46500 for (pixel_x = 0; pixel_x < 4; pixel_x++) {
171 37200 pixels[block_ptr++] = pixels[prev_block_ptr++];
172 }
173 9300 block_ptr += row_inc;
174 9300 prev_block_ptr += row_inc;
175 }
176
3/4
✓ Branch 0 taken 31 times.
✓ Branch 1 taken 2294 times.
✗ Branch 2 not taken.
✓ Branch 3 taken 2325 times.
2325 ADVANCE_BLOCK();
177 }
178 1068 break;
179
180 /* repeat previous pair of blocks n times */
181 case 0x40:
182 case 0x50:
183 n_blocks = GET_BLOCK_COUNT();
184 n_blocks *= 2;
185
186 /* sanity check */
187 if ((row_ptr == 0) && (pixel_ptr < 2 * 4)) {
188 av_log(s->avctx, AV_LOG_ERROR, "encountered repeat block opcode (%02X) but not enough blocks rendered yet\n",
189 opcode & 0xF0);
190 return AVERROR_INVALIDDATA;
191 }
192
193 /* figure out where the previous 2 blocks started */
194 if (pixel_ptr == 0)
195 prev_block_ptr1 = (row_ptr - s->avctx->width * 4) +
196 s->avctx->width - 4 * 2;
197 else if (pixel_ptr == 4)
198 prev_block_ptr1 = (row_ptr - s->avctx->width * 4) + row_inc;
199 else
200 prev_block_ptr1 = row_ptr + pixel_ptr - 4 * 2;
201
202 if (pixel_ptr == 0)
203 prev_block_ptr2 = (row_ptr - s->avctx->width * 4) + row_inc;
204 else
205 prev_block_ptr2 = row_ptr + pixel_ptr - 4;
206
207 prev_block_flag = 0;
208 while (n_blocks--) {
209 block_ptr = row_ptr + pixel_ptr;
210 if (prev_block_flag)
211 prev_block_ptr = prev_block_ptr2;
212 else
213 prev_block_ptr = prev_block_ptr1;
214 prev_block_flag = !prev_block_flag;
215
216 for (pixel_y = 0; pixel_y < 4; pixel_y++) {
217 for (pixel_x = 0; pixel_x < 4; pixel_x++) {
218 pixels[block_ptr++] = pixels[prev_block_ptr++];
219 }
220 block_ptr += row_inc;
221 prev_block_ptr += row_inc;
222 }
223 ADVANCE_BLOCK();
224 }
225 break;
226
227 /* 1-color block encoding */
228 11688 case 0x60:
229 case 0x70:
230
2/2
✓ Branch 0 taken 1082 times.
✓ Branch 1 taken 10606 times.
11688 n_blocks = GET_BLOCK_COUNT();
231 11688 pixel = bytestream2_get_byte(gb);
232
233
2/2
✓ Branch 0 taken 50417 times.
✓ Branch 1 taken 11688 times.
62105 while (n_blocks--) {
234 50417 block_ptr = row_ptr + pixel_ptr;
235
2/2
✓ Branch 0 taken 201668 times.
✓ Branch 1 taken 50417 times.
252085 for (pixel_y = 0; pixel_y < 4; pixel_y++) {
236
2/2
✓ Branch 0 taken 806672 times.
✓ Branch 1 taken 201668 times.
1008340 for (pixel_x = 0; pixel_x < 4; pixel_x++) {
237 806672 pixels[block_ptr++] = pixel;
238 }
239 201668 block_ptr += row_inc;
240 }
241
3/4
✓ Branch 0 taken 631 times.
✓ Branch 1 taken 49786 times.
✗ Branch 2 not taken.
✓ Branch 3 taken 50417 times.
50417 ADVANCE_BLOCK();
242 }
243 11688 break;
244
245 /* 2-color block encoding */
246 17912 case 0x80:
247 case 0x90:
248 17912 n_blocks = (opcode & 0x0F) + 1;
249
250 /* figure out which color pair to use to paint the 2-color block */
251
2/2
✓ Branch 0 taken 5271 times.
✓ Branch 1 taken 12641 times.
17912 if ((opcode & 0xF0) == 0x80) {
252 /* fetch the next 2 colors from bytestream and store in next
253 * available entry in the color pair table */
254
2/2
✓ Branch 0 taken 10542 times.
✓ Branch 1 taken 5271 times.
15813 for (i = 0; i < CPAIR; i++) {
255 10542 pixel = bytestream2_get_byte(gb);
256 10542 color_table_index = CPAIR * color_pair_index + i;
257 10542 s->color_pairs[color_table_index] = pixel;
258 }
259 /* this is the base index to use for this block */
260 5271 color_table_index = CPAIR * color_pair_index;
261 5271 color_pair_index++;
262 /* wraparound */
263
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 5271 times.
5271 if (color_pair_index == COLORS_PER_TABLE)
264 color_pair_index = 0;
265 } else
266 12641 color_table_index = CPAIR * bytestream2_get_byte(gb);
267
268
2/2
✓ Branch 0 taken 18944 times.
✓ Branch 1 taken 17912 times.
36856 while (n_blocks--) {
269 18944 color_flags = bytestream2_get_be16(gb);
270 18944 flag_mask = 0x8000;
271 18944 block_ptr = row_ptr + pixel_ptr;
272
2/2
✓ Branch 0 taken 75776 times.
✓ Branch 1 taken 18944 times.
94720 for (pixel_y = 0; pixel_y < 4; pixel_y++) {
273
2/2
✓ Branch 0 taken 303104 times.
✓ Branch 1 taken 75776 times.
378880 for (pixel_x = 0; pixel_x < 4; pixel_x++) {
274
2/2
✓ Branch 0 taken 121822 times.
✓ Branch 1 taken 181282 times.
303104 if (color_flags & flag_mask)
275 121822 pixel = color_table_index + 1;
276 else
277 181282 pixel = color_table_index;
278 303104 flag_mask >>= 1;
279 303104 pixels[block_ptr++] = s->color_pairs[pixel];
280 }
281 75776 block_ptr += row_inc;
282 }
283
3/4
✓ Branch 0 taken 41 times.
✓ Branch 1 taken 18903 times.
✗ Branch 2 not taken.
✓ Branch 3 taken 18944 times.
18944 ADVANCE_BLOCK();
284 }
285 17912 break;
286
287 /* 4-color block encoding */
288 35882 case 0xA0:
289 case 0xB0:
290 35882 n_blocks = (opcode & 0x0F) + 1;
291
292 /* figure out which color quad to use to paint the 4-color block */
293
2/2
✓ Branch 0 taken 14534 times.
✓ Branch 1 taken 21348 times.
35882 if ((opcode & 0xF0) == 0xA0) {
294 /* fetch the next 4 colors from bytestream and store in next
295 * available entry in the color quad table */
296
2/2
✓ Branch 0 taken 58136 times.
✓ Branch 1 taken 14534 times.
72670 for (i = 0; i < CQUAD; i++) {
297 58136 pixel = bytestream2_get_byte(gb);
298 58136 color_table_index = CQUAD * color_quad_index + i;
299 58136 s->color_quads[color_table_index] = pixel;
300 }
301 /* this is the base index to use for this block */
302 14534 color_table_index = CQUAD * color_quad_index;
303 14534 color_quad_index++;
304 /* wraparound */
305
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 14534 times.
14534 if (color_quad_index == COLORS_PER_TABLE)
306 color_quad_index = 0;
307 } else
308 21348 color_table_index = CQUAD * bytestream2_get_byte(gb);
309
310
2/2
✓ Branch 0 taken 41159 times.
✓ Branch 1 taken 35882 times.
77041 while (n_blocks--) {
311 41159 color_flags = bytestream2_get_be32(gb);
312 /* flag mask actually acts as a bit shift count here */
313 41159 flag_mask = 30;
314 41159 block_ptr = row_ptr + pixel_ptr;
315
2/2
✓ Branch 0 taken 164636 times.
✓ Branch 1 taken 41159 times.
205795 for (pixel_y = 0; pixel_y < 4; pixel_y++) {
316
2/2
✓ Branch 0 taken 658544 times.
✓ Branch 1 taken 164636 times.
823180 for (pixel_x = 0; pixel_x < 4; pixel_x++) {
317 658544 pixel = color_table_index +
318 658544 ((color_flags >> flag_mask) & 0x03);
319 658544 flag_mask -= 2;
320 658544 pixels[block_ptr++] = s->color_quads[pixel];
321 }
322 164636 block_ptr += row_inc;
323 }
324
3/4
✓ Branch 0 taken 78 times.
✓ Branch 1 taken 41081 times.
✗ Branch 2 not taken.
✓ Branch 3 taken 41159 times.
41159 ADVANCE_BLOCK();
325 }
326 35882 break;
327
328 /* 8-color block encoding */
329 33474 case 0xC0:
330 case 0xD0:
331 33474 n_blocks = (opcode & 0x0F) + 1;
332
333 /* figure out which color octet to use to paint the 8-color block */
334
2/2
✓ Branch 0 taken 10987 times.
✓ Branch 1 taken 22487 times.
33474 if ((opcode & 0xF0) == 0xC0) {
335 /* fetch the next 8 colors from bytestream and store in next
336 * available entry in the color octet table */
337
2/2
✓ Branch 0 taken 87896 times.
✓ Branch 1 taken 10987 times.
98883 for (i = 0; i < COCTET; i++) {
338 87896 pixel = bytestream2_get_byte(gb);
339 87896 color_table_index = COCTET * color_octet_index + i;
340 87896 s->color_octets[color_table_index] = pixel;
341 }
342 /* this is the base index to use for this block */
343 10987 color_table_index = COCTET * color_octet_index;
344 10987 color_octet_index++;
345 /* wraparound */
346
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 10987 times.
10987 if (color_octet_index == COLORS_PER_TABLE)
347 color_octet_index = 0;
348 } else
349 22487 color_table_index = COCTET * bytestream2_get_byte(gb);
350
351
2/2
✓ Branch 0 taken 42573 times.
✓ Branch 1 taken 33474 times.
76047 while (n_blocks--) {
352 /*
353 For this input of 6 hex bytes:
354 01 23 45 67 89 AB
355 Mangle it to this output:
356 flags_a = xx012456, flags_b = xx89A37B
357 */
358 /* build the color flags */
359 42573 int val1 = bytestream2_get_be16(gb);
360 42573 int val2 = bytestream2_get_be16(gb);
361 42573 int val3 = bytestream2_get_be16(gb);
362 42573 color_flags_a = ((val1 & 0xFFF0) << 8) | (val2 >> 4);
363 42573 color_flags_b = ((val3 & 0xFFF0) << 8) |
364 42573 ((val1 & 0x0F) << 8) | ((val2 & 0x0F) << 4) | (val3 & 0x0F);
365
366 42573 color_flags = color_flags_a;
367 /* flag mask actually acts as a bit shift count here */
368 42573 flag_mask = 21;
369 42573 block_ptr = row_ptr + pixel_ptr;
370
2/2
✓ Branch 0 taken 170292 times.
✓ Branch 1 taken 42573 times.
212865 for (pixel_y = 0; pixel_y < 4; pixel_y++) {
371 /* reload flags at third row (iteration pixel_y == 2) */
372
2/2
✓ Branch 0 taken 42573 times.
✓ Branch 1 taken 127719 times.
170292 if (pixel_y == 2) {
373 42573 color_flags = color_flags_b;
374 42573 flag_mask = 21;
375 }
376
2/2
✓ Branch 0 taken 681168 times.
✓ Branch 1 taken 170292 times.
851460 for (pixel_x = 0; pixel_x < 4; pixel_x++) {
377 681168 pixel = color_table_index +
378 681168 ((color_flags >> flag_mask) & 0x07);
379 681168 flag_mask -= 3;
380 681168 pixels[block_ptr++] = s->color_octets[pixel];
381 }
382 170292 block_ptr += row_inc;
383 }
384
3/4
✓ Branch 0 taken 44 times.
✓ Branch 1 taken 42529 times.
✗ Branch 2 not taken.
✓ Branch 3 taken 42573 times.
42573 ADVANCE_BLOCK();
385 }
386 33474 break;
387
388 /* 16-color block encoding (every pixel is a different color) */
389 2043 case 0xE0:
390 case 0xF0:
391 2043 n_blocks = (opcode & 0x0F) + 1;
392
393
2/2
✓ Branch 0 taken 2197 times.
✓ Branch 1 taken 2043 times.
4240 while (n_blocks--) {
394 2197 block_ptr = row_ptr + pixel_ptr;
395
2/2
✓ Branch 0 taken 8788 times.
✓ Branch 1 taken 2197 times.
10985 for (pixel_y = 0; pixel_y < 4; pixel_y++) {
396
2/2
✓ Branch 0 taken 35152 times.
✓ Branch 1 taken 8788 times.
43940 for (pixel_x = 0; pixel_x < 4; pixel_x++) {
397 35152 pixels[block_ptr++] = bytestream2_get_byte(gb);
398 }
399 8788 block_ptr += row_inc;
400 }
401
2/4
✗ Branch 0 not taken.
✓ Branch 1 taken 2197 times.
✗ Branch 2 not taken.
✓ Branch 3 taken 2197 times.
2197 ADVANCE_BLOCK();
402 }
403 2043 break;
404 }
405 }
406
407 120 return 0;
408 }
409
410 2 static av_cold int smc_decode_init(AVCodecContext *avctx)
411 {
412 2 SmcContext *s = avctx->priv_data;
413
414 2 s->avctx = avctx;
415 2 avctx->pix_fmt = AV_PIX_FMT_PAL8;
416
417 2 s->frame = av_frame_alloc();
418
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 2 times.
2 if (!s->frame)
419 return AVERROR(ENOMEM);
420
421 2 return 0;
422 }
423
424 120 static int smc_decode_frame(AVCodecContext *avctx, AVFrame *rframe,
425 int *got_frame, AVPacket *avpkt)
426 {
427 120 const uint8_t *buf = avpkt->data;
428 120 int buf_size = avpkt->size;
429 120 SmcContext *s = avctx->priv_data;
430 GetByteContext gb;
431 int ret;
432 120 int total_blocks = ((s->avctx->width + 3) / 4) * ((s->avctx->height + 3) / 4);
433
434
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 120 times.
120 if (total_blocks / 1024 > avpkt->size)
435 return AVERROR_INVALIDDATA;
436
437
1/2
✗ Branch 1 not taken.
✓ Branch 2 taken 120 times.
120 if ((ret = ff_reget_buffer(avctx, s->frame, 0)) < 0)
438 return ret;
439
440 120 s->frame->palette_has_changed = ff_copy_palette(s->pal, avpkt, avctx);
441
442 120 bytestream2_init(&gb, buf, buf_size);
443 120 ret = smc_decode_stream(s, &gb);
444
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 120 times.
120 if (ret < 0)
445 return ret;
446
447 120 *got_frame = 1;
448
1/2
✗ Branch 1 not taken.
✓ Branch 2 taken 120 times.
120 if ((ret = av_frame_ref(rframe, s->frame)) < 0)
449 return ret;
450
451 /* always report that the buffer was completely consumed */
452 120 return buf_size;
453 }
454
455 2 static av_cold int smc_decode_end(AVCodecContext *avctx)
456 {
457 2 SmcContext *s = avctx->priv_data;
458
459 2 av_frame_free(&s->frame);
460
461 2 return 0;
462 }
463
464 const FFCodec ff_smc_decoder = {
465 .p.name = "smc",
466 CODEC_LONG_NAME("QuickTime Graphics (SMC)"),
467 .p.type = AVMEDIA_TYPE_VIDEO,
468 .p.id = AV_CODEC_ID_SMC,
469 .priv_data_size = sizeof(SmcContext),
470 .init = smc_decode_init,
471 .close = smc_decode_end,
472 FF_CODEC_DECODE_CB(smc_decode_frame),
473 .p.capabilities = AV_CODEC_CAP_DR1,
474 };
475