FFmpeg coverage


Directory: ../../../ffmpeg/
File: src/libavcodec/gemdec.c
Date: 2025-04-25 22:50:00
Exec Total Coverage
Lines: 0 202 0.0%
Functions: 0 4 0.0%
Branches: 0 184 0.0%

Line Branch Exec Source
1 /*
2 * GEM Raster image decoder
3 * Copyright (c) 2021 Peter Ross (pross@xvid.org)
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 * GEM Raster image 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 static const uint32_t gem_color_palette[16]={
34 0xFFFFFFFF, 0xFFFF0000, 0xFF00FF00, 0xFFFFFF00,
35 0xFF0000FF, 0xFFFF00FF, 0xFF00FFFF, 0xFFAEAEAE,
36 0xFF555555, 0xFFAE0000, 0xFF00AE00, 0xFFAEAE00,
37 0xFF0000AE, 0xFFAE00AE, 0xFF00AEAE, 0xFF000000,
38 };
39
40 static const uint8_t gem_gray[256]={
41 0xFF, 0x7F, 0xBF, 0x3F, 0xDF, 0x5F, 0x9F, 0x1F, 0xEF, 0x6F, 0xAF, 0x2F, 0xCF, 0x4F, 0x8F, 0x0F,
42 0xF7, 0x77, 0xB7, 0x37, 0xD7, 0x57, 0x97, 0x17, 0xE7, 0x67, 0xA7, 0x27, 0xC7, 0x47, 0x87, 0x07,
43 0xFB, 0x7B, 0xBB, 0x3B, 0xDB, 0x5B, 0x9B, 0x1B, 0xEB, 0x6B, 0xAB, 0x2B, 0xCB, 0x4B, 0x8B, 0x0B,
44 0xF3, 0x73, 0xB3, 0x33, 0xD3, 0x53, 0x93, 0x13, 0xE3, 0x63, 0xA3, 0x23, 0xC3, 0x43, 0x83, 0x03,
45 0xFD, 0x7D, 0xBD, 0x3D, 0xDD, 0x5D, 0x9D, 0x1D, 0xED, 0x6D, 0xAD, 0x2D, 0xCD, 0x4D, 0x8D, 0x0D,
46 0xF5, 0x75, 0xB5, 0x35, 0xD5, 0x55, 0x95, 0x15, 0xE5, 0x65, 0xA5, 0x25, 0xC5, 0x45, 0x85, 0x05,
47 0xF9, 0x79, 0xB9, 0x39, 0xD9, 0x59, 0x99, 0x19, 0xE9, 0x69, 0xA9, 0x29, 0xC9, 0x49, 0x89, 0x09,
48 0xF1, 0x71, 0xB1, 0x31, 0xD1, 0x51, 0x91, 0x11, 0xE1, 0x61, 0xA1, 0x21, 0xC1, 0x41, 0x81, 0x01,
49 0xFE, 0x7E, 0xBE, 0x3E, 0xDE, 0x5E, 0x9E, 0x1E, 0xEE, 0x6E, 0xAE, 0x2E, 0xCE, 0x4E, 0x8E, 0x0E,
50 0xF6, 0x76, 0xB6, 0x36, 0xD6, 0x56, 0x96, 0x16, 0xE6, 0x66, 0xA6, 0x26, 0xC6, 0x46, 0x86, 0x06,
51 0xFA, 0x7A, 0xBA, 0x3A, 0xDA, 0x5A, 0x9A, 0x1A, 0xEA, 0x6A, 0xAA, 0x2A, 0xCA, 0x4A, 0x8A, 0x0A,
52 0xF2, 0x72, 0xB2, 0x32, 0xD2, 0x52, 0x92, 0x12, 0xE2, 0x62, 0xA2, 0x22, 0xC2, 0x42, 0x82, 0x02,
53 0xFC, 0x7C, 0xBC, 0x3C, 0xDC, 0x5C, 0x9C, 0x1C, 0xEC, 0x6C, 0xAC, 0x2C, 0xCC, 0x4C, 0x8C, 0x0C,
54 0xF4, 0x74, 0xB4, 0x34, 0xD4, 0x54, 0x94, 0x14, 0xE4, 0x64, 0xA4, 0x24, 0xC4, 0x44, 0x84, 0x04,
55 0xF8, 0x78, 0xB8, 0x38, 0xD8, 0x58, 0x98, 0x18, 0xE8, 0x68, 0xA8, 0x28, 0xC8, 0x48, 0x88, 0x08,
56 0xF0, 0x70, 0xB0, 0x30, 0xD0, 0x50, 0x90, 0x10, 0xE0, 0x60, 0xA0, 0x20, 0xC0, 0x40, 0x80, 0x00,
57 };
58
59 typedef struct {
60 int y, pl, x, vdup;
61 } State;
62
63 static void put_lines_bits(AVCodecContext *avctx, int planes, int row_width, int pixel_size, State * state, uint8_t * row, AVFrame *p)
64 {
65 int pl_byte = state->pl / 8;
66 int pl_bit = state->pl & 7;
67 for (int y = 0; y < state->vdup && (state->y + y) < avctx->height; y++)
68 for (int x = 0; x < row_width; x++)
69 for (int i = 7; i >= 0 && x * 8 + 7 - i < avctx->width; i--)
70 p->data[0][ (state->y + y) * p->linesize[0] + (x * 8 + 7 - i) * pixel_size + pl_byte] |= !!(row[x] & (1 << i)) << pl_bit;
71
72 state->pl++;
73 if (state->pl >= planes) {
74 state->pl = 0;
75 state->y += state->vdup;
76 state->vdup = 1;
77 }
78 }
79
80 static void put_lines_bytes(AVCodecContext *avctx, int planes, int row_width, int pixel_size, State * state, uint8_t * row, AVFrame *p)
81 {
82 for (int y = 0; y < state->vdup && (state->y + y) < avctx->height; y++)
83 memcpy(p->data[0] + (state->y + y) * p->linesize[0], row, avctx->width * pixel_size);
84
85 state->y += state->vdup;
86 state->vdup = 1;
87 }
88
89 static int gem_decode_frame(AVCodecContext *avctx, AVFrame *p,
90 int *got_frame, AVPacket *avpkt)
91 {
92 const uint8_t *buf = avpkt->data;
93 int buf_size = avpkt->size;
94 const uint8_t *buf_end = buf + buf_size;
95 int header_size, planes, pattern_size, tag = 0, count_scalar = 1, ret;
96 unsigned int x, count, v;
97 GetByteContext gb;
98 uint32_t *palette;
99 const uint8_t * b;
100 uint8_t * row;
101 int row_width, pixel_size;
102 State state = {.y = 0, .pl = 0, .x = 0, .vdup = 1};
103 void (*put_lines)(AVCodecContext *avctx, int planes, int row_width, int pixel_size, State * state, uint8_t * row, AVFrame *p);
104 int width, height;
105
106 if (buf_size <= 16)
107 return AVERROR_INVALIDDATA;
108
109 bytestream2_init(&gb, buf + 2, buf_size - 2);
110 header_size = bytestream2_get_be16(&gb);
111 if (header_size < 8 || buf_size <= header_size * 2)
112 return AVERROR_INVALIDDATA;
113
114 planes = bytestream2_get_be16(&gb);
115 pattern_size = bytestream2_get_be16(&gb);
116 avctx->sample_aspect_ratio.num = bytestream2_get_be16(&gb);
117 avctx->sample_aspect_ratio.den = bytestream2_get_be16(&gb);
118 width = bytestream2_get_be16(&gb);
119 height = bytestream2_get_be16(&gb);
120 ret = ff_set_dimensions(avctx, width, height);
121 if (ret < 0)
122 return ret;
123
124 row_width = (avctx->width + 7) / 8;
125 put_lines = put_lines_bits;
126
127 if (header_size == 9) {
128 count_scalar = bytestream2_get_be16(&gb);
129 if (count_scalar != 3) {
130 avpriv_request_sample(avctx, "count_scalar=%d", count_scalar);
131 return AVERROR_PATCHWELCOME;
132 }
133 planes = 24;
134 avctx->pix_fmt = AV_PIX_FMT_BGR24;
135 pixel_size = 3;
136 } else if (planes == 15) {
137 #if HAVE_BIGENDIAN
138 avctx->pix_fmt = AV_PIX_FMT_BGR555BE;
139 #else
140 avctx->pix_fmt = AV_PIX_FMT_BGR555LE;
141 #endif
142 pixel_size = 2;
143 } else if (planes == 16) {
144 avctx->pix_fmt = AV_PIX_FMT_RGB565BE;
145 pixel_size = 2;
146 } else if (planes == 24) {
147 avctx->pix_fmt = AV_PIX_FMT_RGB24;
148 pixel_size = 3;
149 } else if (planes == 32) {
150 avctx->pix_fmt = AV_PIX_FMT_0RGB;
151 pixel_size = 4;
152 } else {
153 avctx->pix_fmt = AV_PIX_FMT_PAL8;
154 pixel_size = 1;
155 }
156
157 if (header_size >= 11)
158 tag = bytestream2_peek_be32(&gb);
159
160 if (tag == AV_RB32("STTT")) {
161 if (planes != 4) {
162 avpriv_request_sample(avctx, "STTT planes=%d", planes);
163 return AVERROR_PATCHWELCOME;
164 }
165 } else if (tag == AV_RB32("TIMG")) {
166 if (planes != 15) {
167 avpriv_request_sample(avctx, "TIMG planes=%d", planes);
168 return AVERROR_PATCHWELCOME;
169 }
170 } else if (tag == AV_RB32("XIMG")) {
171 if (planes != 1 && planes != 2 && planes != 4 && planes != 8 && planes != 16 && planes != 24 && planes != 32) {
172 avpriv_request_sample(avctx, "XIMG planes=%d", planes);
173 return AVERROR_PATCHWELCOME;
174 }
175 } else if (planes != 1 && planes != 2 && planes != 3 && planes != 4 && planes != 8 && planes != 16 && planes != 24) {
176 avpriv_request_sample(avctx, "planes=%d", planes);
177 return AVERROR_PATCHWELCOME;
178 }
179
180 if ((ret = ff_get_buffer(avctx, p, 0)) < 0)
181 return ret;
182
183 p->pict_type = AV_PICTURE_TYPE_I;
184 p->flags |= AV_FRAME_FLAG_KEY;
185 palette = (uint32_t *)p->data[1];
186
187 if (tag == AV_RB32("STTT")) {
188 bytestream2_skip(&gb, 6);
189 if (planes == 4) {
190 for (int i = 0; i < (1 << planes); i++) {
191 int v = bytestream2_get_be16(&gb);
192 int r = ((v >> 8) & 0x7) << 5;
193 int g = ((v >> 4) & 0x7) << 5;
194 int b = ((v ) & 0x7) << 5;
195 palette[i] = 0xFF000000 | r << 16 | g << 8 | b;
196 }
197 } else {
198 av_assert0(0);
199 }
200 } else if (tag == AV_RB32("TIMG")) {
201 bytestream2_skip(&gb, 4);
202 if (planes != 15) {
203 av_assert0(0);
204 }
205 } else if (tag == AV_RB32("XIMG")) {
206 bytestream2_skip(&gb, 6);
207 if (planes == 1 || planes == 2 || planes == 4 || planes == 8) {
208 for (int i = 0; i < (1 << planes); i++) {
209 int r = (bytestream2_get_be16(&gb) * 51 + 100) / 200;
210 int g = (bytestream2_get_be16(&gb) * 51 + 100) / 200;
211 int b = (bytestream2_get_be16(&gb) * 51 + 100) / 200;
212 palette[i] = 0xFF000000 | r << 16 | g << 8 | b;
213 }
214 } else if (planes == 16) {
215 planes = 1;
216 row_width = ((avctx->width + 7)/8)*8 * pixel_size;
217 put_lines = put_lines_bytes;
218 } else if (planes == 24) {
219 planes = 1;
220 row_width = ((avctx->width + 15)/16)*16 * pixel_size;
221 put_lines = put_lines_bytes;
222 } else if (planes == 32) {
223 planes = 1;
224 row_width = avctx->width * pixel_size;
225 put_lines = put_lines_bytes;
226 } else {
227 av_assert0(0);
228 }
229 } else if (planes == 1) {
230 palette[0] = 0xFFFFFFFF;
231 palette[1] = 0xFF000000;
232 } else if (planes == 2 || planes == 3 || planes == 4) {
233 if (header_size == 9 + (1 << planes)) {
234 bytestream2_skip(&gb, 2);
235 for (int i = 0; i < (1 << planes); i++) {
236 int v = bytestream2_get_be16(&gb);
237 int r = ((v >> 8) & 0x7) << 5;
238 int g = ((v >> 4) & 0x7) << 5;
239 int b = ((v ) & 0x7) << 5;
240 palette[i] = 0xFF000000 | r << 16 | g << 8 | b;
241 }
242 } else
243 memcpy(palette, gem_color_palette, sizeof(gem_color_palette));
244 } else if (planes == 8) {
245 for (int i = 0; i < 256; i++)
246 palette[i] = 0xFF000000 | (gem_gray[i]<<16) | (gem_gray[i]<<8) | gem_gray[i];
247 } else if (planes == 16) {
248 planes = 1;
249 row_width = avctx->width * pixel_size;
250 put_lines = put_lines_bytes;
251 } else if (planes == 24) {
252 planes = 1;
253 row_width = avctx->width * pixel_size;
254 put_lines = put_lines_bytes;
255 } else
256 av_assert0(0);
257
258 ret = av_reallocp_array(&avctx->priv_data, planes, row_width);
259 if (ret < 0)
260 return ret;
261 row = avctx->priv_data;
262
263 memset(p->data[0], 0, avctx->height * p->linesize[0]);
264 b = buf + header_size * 2;
265 x = 0;
266
267 #define SKIP \
268 do { \
269 x++; \
270 if (x >= row_width) { \
271 put_lines(avctx, planes, row_width, pixel_size, &state, row + state.pl * row_width, p); \
272 if (state.y >= avctx->height) goto abort; \
273 x = 0; \
274 } \
275 } while(0)
276
277 #define PUT(v) \
278 do { \
279 row[state.pl * row_width + x++] = v; \
280 if (x >= row_width) { \
281 put_lines(avctx, planes, row_width, pixel_size, &state, row + state.pl * row_width, p); \
282 if (state.y >= avctx->height) goto abort; \
283 x = 0; \
284 } \
285 } while(0)
286
287 while(b < buf_end) {
288 int opcode = *b++;
289 if (opcode == 0x80) { /* copy */
290 if (b >= buf_end)
291 goto abort;
292 count = *b++;
293 if (!count)
294 count = 256;
295 count *= count_scalar;
296 for (int j = 0; j < count; j++) {
297 if (b >= buf_end)
298 goto abort;
299 PUT(*b++);
300 }
301 } else if (opcode) { /* run */
302 count = opcode & 0x7f;
303 if (!count)
304 count = 256;
305 count *= count_scalar;
306 v = opcode & 0x80 ? 0xFF : 0x00;
307 for (int i = 0; i < count; i++)
308 PUT(v);
309 } else {
310 if (b >= buf_end)
311 goto abort;
312 count = *b++;
313 if (count) { /* pattern */
314 if (b > buf_end - pattern_size)
315 goto abort;
316
317 count *= count_scalar;
318 for (int j = 0; j < count; j++)
319 for (int k = 0; k < pattern_size; k++)
320 PUT(b[k]);
321
322 b += pattern_size;
323 } else {
324 if (b >= buf_end)
325 goto abort;
326 count = *b++;
327 if (count == 0xFF) { /* vertical duplication */
328 if (b >= buf_end)
329 goto abort;
330 state.vdup = *b++;
331 if (!state.vdup)
332 state.vdup = 256;
333 } else { /* horizontal duplication */
334 for (int i = 0; i < count + 1; i++)
335 SKIP;
336 }
337 }
338 }
339 }
340
341 abort:
342
343 *got_frame = 1;
344 return buf_size;
345 }
346
347 static av_cold int gem_close(AVCodecContext *avctx)
348 {
349 av_freep(&avctx->priv_data);
350 return 0;
351 }
352
353 const FFCodec ff_gem_decoder = {
354 .p.name = "gem",
355 CODEC_LONG_NAME("GEM Raster image"),
356 .p.type = AVMEDIA_TYPE_VIDEO,
357 .p.id = AV_CODEC_ID_GEM,
358 .p.capabilities = AV_CODEC_CAP_DR1,
359 FF_CODEC_DECODE_CB(gem_decode_frame),
360 .close = gem_close,
361 };
362