FFmpeg: libavcodec/pafvideo.c Source File

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libavcodec

pafvideo.c

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1 /*

2 * Packed Animation File video decoder

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 */

22 #include "libavutil/imgutils.h"

24 #include "avcodec.h"

25 #include "bytestream.h"

26 #include "copy_block.h"

27 #include "internal.h"

30 static const uint8_t block_sequences[16][8] = {

31 { 0, 0, 0, 0, 0, 0, 0, 0 },

32 { 2, 0, 0, 0, 0, 0, 0, 0 },

33 { 5, 7, 0, 0, 0, 0, 0, 0 },

34 { 5, 0, 0, 0, 0, 0, 0, 0 },

35 { 6, 0, 0, 0, 0, 0, 0, 0 },

36 { 5, 7, 5, 7, 0, 0, 0, 0 },

37 { 5, 7, 5, 0, 0, 0, 0, 0 },

38 { 5, 7, 6, 0, 0, 0, 0, 0 },

39 { 5, 5, 0, 0, 0, 0, 0, 0 },

40 { 3, 0, 0, 0, 0, 0, 0, 0 },

41 { 6, 6, 0, 0, 0, 0, 0, 0 },

42 { 2, 4, 0, 0, 0, 0, 0, 0 },

43 { 2, 4, 5, 7, 0, 0, 0, 0 },

44 { 2, 4, 5, 0, 0, 0, 0, 0 },

45 { 2, 4, 6, 0, 0, 0, 0, 0 },

46 { 2, 4, 5, 7, 5, 7, 0, 0 },

47 };

49 typedef struct PAFVideoDecContext {

50 AVFrame *pic;

51 GetByteContext gb;

53 int width;

54 int height;

56 int current_frame;

57 uint8_t *frame[4];

58 int frame_size;

59 int video_size;

61 uint8_t *opcodes;

62 } PAFVideoDecContext;

64 static av_cold int paf_video_close(AVCodecContext *avctx)

65 {

66 PAFVideoDecContext *c = avctx->priv_data;

67 int i;

69 av_frame_free(&c->pic);

71 for (i = 0; i < 4; i++)

72 av_freep(&c->frame[i]);

74 return 0;

75 }

77 static av_cold int paf_video_init(AVCodecContext *avctx)

78 {

79 PAFVideoDecContext *c = avctx->priv_data;

80 int i;

82 c->width = avctx->width;

83 c->height = avctx->height;

85 if (avctx->height & 3 || avctx->width & 3) {

86 av_log(avctx, AV_LOG_ERROR,

87 "width %d and height %d must be multiplie of 4.\n",

88 avctx->width, avctx->height);

89 return AVERROR_INVALIDDATA;

90 }

92 avctx->pix_fmt = AV_PIX_FMT_PAL8;

94 c->pic = av_frame_alloc();

95 if (!c->pic)

96 return AVERROR(ENOMEM);

98 c->frame_size = avctx->width * FFALIGN(avctx->height, 256);

99 c->video_size = avctx->width * avctx->height;

100 for (i = 0; i < 4; i++) {

101 c->frame[i] = av_mallocz(c->frame_size);

102 if (!c->frame[i]) {

103 paf_video_close(avctx);

104 return AVERROR(ENOMEM);

105 }

106 }

107

108 return 0;

109 }

110

111 static void read4x4block(PAFVideoDecContext *c, uint8_t *dst, int width)

112 {

113 int i;

114

115 for (i = 0; i < 4; i++) {

116 bytestream2_get_buffer(&c->gb, dst, 4);

117 dst += width;

118 }

119 }

120

121 static void copy_color_mask(uint8_t *dst, int width, uint8_t mask, uint8_t color)

122 {

123 int i;

124

125 for (i = 0; i < 4; i++) {

126 if (mask & (1 << 7 - i))

127 dst[i] = color;

128 if (mask & (1 << 3 - i))

129 dst[width + i] = color;

130 }

131 }

132

133 static void copy_src_mask(uint8_t *dst, int width, uint8_t mask, const uint8_t *src)

134 {

135 int i;

136

137 for (i = 0; i < 4; i++) {

138 if (mask & (1 << 7 - i))

139 dst[i] = src[i];

140 if (mask & (1 << 3 - i))

141 dst[width + i] = src[width + i];

142 }

143 }

144

145 static void set_src_position(PAFVideoDecContext *c,

146 const uint8_t **p,

147 const uint8_t **pend)

148 {

149 int val = bytestream2_get_be16(&c->gb);

150 int page = val >> 14;

151 int x = (val & 0x7F);

152 int y = ((val >> 7) & 0x7F);

153

154 *p = c->frame[page] + x * 2 + y * 2 * c->width;

155 *pend = c->frame[page] + c->frame_size;

156 }

157

158 static int decode_0(PAFVideoDecContext *c, uint8_t *pkt, uint8_t code)

159 {

160 uint32_t opcode_size, offset;

161 uint8_t *dst, *dend, mask = 0, color = 0;

162 const uint8_t *src, *send, *opcodes;

163 int i, j, op = 0;

164

165 i = bytestream2_get_byte(&c->gb);

166 if (i) {

167 if (code & 0x10) {

168 int align;

169

170 align = bytestream2_tell(&c->gb) & 3;

171 if (align)

172 bytestream2_skip(&c->gb, 4 - align);

173 }

174 do {

175 int page, val, x, y;

176 val = bytestream2_get_be16(&c->gb);

177 page = val >> 14;

178 x = (val & 0x7F) * 2;

179 y = ((val >> 7) & 0x7F) * 2;

180 dst = c->frame[page] + x + y * c->width;

181 dend = c->frame[page] + c->frame_size;

182 offset = (x & 0x7F) * 2;

183 j = bytestream2_get_le16(&c->gb) + offset;

184 do {

185 offset++;

186 if (dst + 3 * c->width + 4 > dend)

187 return AVERROR_INVALIDDATA;

188 read4x4block(c, dst, c->width);

189 if ((offset & 0x3F) == 0)

190 dst += c->width * 3;

191 dst += 4;

192 } while (offset < j);

193 } while (--i);

194 }

195

196 dst = c->frame[c->current_frame];

197 dend = c->frame[c->current_frame] + c->frame_size;

198 do {

199 set_src_position(c, &src, &send);

200 if ((src + 3 * c->width + 4 > send) ||

201 (dst + 3 * c->width + 4 > dend))

202 return AVERROR_INVALIDDATA;

203 copy_block4(dst, src, c->width, c->width, 4);

204 i++;

205 if ((i & 0x3F) == 0)

206 dst += c->width * 3;

207 dst += 4;

208 } while (i < c->video_size / 16);

209

210 opcode_size = bytestream2_get_le16(&c->gb);

211 bytestream2_skip(&c->gb, 2);

212

213 if (bytestream2_get_bytes_left(&c->gb) < opcode_size)

214 return AVERROR_INVALIDDATA;

215

216 opcodes = pkt + bytestream2_tell(&c->gb);

217 bytestream2_skipu(&c->gb, opcode_size);

218

219 dst = c->frame[c->current_frame];

220

221 for (i = 0; i < c->height; i += 4, dst += c->width * 3)

222 for (j = 0; j < c->width; j += 4, dst += 4) {

223 int opcode, k = 0;

224 if (op > opcode_size)

225 return AVERROR_INVALIDDATA;

226 if (j & 4) {

227 opcode = opcodes[op] & 15;

228 op++;

229 } else {

230 opcode = opcodes[op] >> 4;

231 }

232

233 while (block_sequences[opcode][k]) {

234 offset = c->width * 2;

235 code = block_sequences[opcode][k++];

236

237 switch (code) {

238 case 2:

239 offset = 0;

240 case 3:

241 color = bytestream2_get_byte(&c->gb);

242 case 4:

243 mask = bytestream2_get_byte(&c->gb);

244 copy_color_mask(dst + offset, c->width, mask, color);

245 break;

246 case 5:

247 offset = 0;

248 case 6:

249 set_src_position(c, &src, &send);

250 case 7:

251 if (src + offset + c->width + 4 > send)

252 return AVERROR_INVALIDDATA;

253 mask = bytestream2_get_byte(&c->gb);

254 copy_src_mask(dst + offset, c->width, mask, src + offset);

255 break;

256 }

257 }

258 }

259

260 return 0;

261 }

262

263 static int paf_video_decode(AVCodecContext *avctx, void *data,

264 int *got_frame, AVPacket *pkt)

265 {

266 PAFVideoDecContext *c = avctx->priv_data;

267 uint8_t code, *dst, *end;

268 int i, frame, ret;

269

270 if ((ret = ff_reget_buffer(avctx, c->pic)) < 0)

271 return ret;

272

273 bytestream2_init(&c->gb, pkt->data, pkt->size);

274

275 code = bytestream2_get_byte(&c->gb);

276 if (code & 0x20) { // frame is keyframe

277 for (i = 0; i < 4; i++)

278 memset(c->frame[i], 0, c->frame_size);

279

280 memset(c->pic->data[1], 0, AVPALETTE_SIZE);

281 c->current_frame = 0;

282 c->pic->key_frame = 1;

283 c->pic->pict_type = AV_PICTURE_TYPE_I;

284 } else {

285 c->pic->key_frame = 0;

286 c->pic->pict_type = AV_PICTURE_TYPE_P;

287 }

288

289 if (code & 0x40) { // palette update

290 uint32_t *out = (uint32_t *)c->pic->data[1];

291 int index, count;

292

293 index = bytestream2_get_byte(&c->gb);

294 count = bytestream2_get_byte(&c->gb) + 1;

295

296 if (index + count > 256)

297 return AVERROR_INVALIDDATA;

298 if (bytestream2_get_bytes_left(&c->gb) < 3 * count)

299 return AVERROR_INVALIDDATA;

300

301 out += index;

302 for (i = 0; i < count; i++) {

303 unsigned r, g, b;

304

305 r = bytestream2_get_byteu(&c->gb);

306 r = r << 2 | r >> 4;

307 g = bytestream2_get_byteu(&c->gb);

308 g = g << 2 | g >> 4;

309 b = bytestream2_get_byteu(&c->gb);

310 b = b << 2 | b >> 4;

311 *out++ = (0xFFU << 24) | (r << 16) | (g << 8) | b;

312 }

313 c->pic->palette_has_changed = 1;

314 }

315

316 switch (code & 0x0F) {

317 case 0:

318 /* Block-based motion compensation using 4x4 blocks with either

319 * horizontal or vertical vectors; might incorporate VQ as well. */

320 if ((ret = decode_0(c, pkt->data, code)) < 0)

321 return ret;

322 break;

323 case 1:

324 /* Uncompressed data. This mode specifies that (width * height) bytes

325 * should be copied directly from the encoded buffer into the output. */

326 dst = c->frame[c->current_frame];

327 // possibly chunk length data

328 bytestream2_skip(&c->gb, 2);

329 if (bytestream2_get_bytes_left(&c->gb) < c->video_size)

330 return AVERROR_INVALIDDATA;

331 bytestream2_get_bufferu(&c->gb, dst, c->video_size);

332 break;

333 case 2:

334 /* Copy reference frame: Consume the next byte in the stream as the

335 * reference frame (which should be 0, 1, 2, or 3, and should not be

336 * the same as the current frame number). */

337 frame = bytestream2_get_byte(&c->gb);

338 if (frame > 3)

339 return AVERROR_INVALIDDATA;

340 if (frame != c->current_frame)

341 memcpy(c->frame[c->current_frame], c->frame[frame], c->frame_size);

342 break;

343 case 4:

344 /* Run length encoding.*/

345 dst = c->frame[c->current_frame];

346 end = dst + c->video_size;

347

348 bytestream2_skip(&c->gb, 2);

349

350 while (dst < end) {

351 int8_t code;

352 int count;

353

354 if (bytestream2_get_bytes_left(&c->gb) < 2)

355 return AVERROR_INVALIDDATA;

356

357 code = bytestream2_get_byteu(&c->gb);

358 count = FFABS(code) + 1;

359

360 if (dst + count > end)

361 return AVERROR_INVALIDDATA;

362 if (code < 0)

363 memset(dst, bytestream2_get_byteu(&c->gb), count);

364 else

365 bytestream2_get_buffer(&c->gb, dst, count);

366 dst += count;

367 }

368 break;

369 default:

370 avpriv_request_sample(avctx, "unknown/invalid code");

371 return AVERROR_INVALIDDATA;

372 }

373

374 av_image_copy_plane(c->pic->data[0], c->pic->linesize[0],

375 c->frame[c->current_frame], c->width,

376 c->width, c->height);

377

378 c->current_frame = (c->current_frame + 1) & 3;

379 if ((ret = av_frame_ref(data, c->pic)) < 0)

380 return ret;

381

382 *got_frame = 1;

383

384 return pkt->size;

385 }

386

387 AVCodec ff_paf_video_decoder = {

388 .name = "paf_video",

389 .long_name = NULL_IF_CONFIG_SMALL("Amazing Studio Packed Animation File Video"),

390 .type = AVMEDIA_TYPE_VIDEO,

391 .id = AV_CODEC_ID_PAF_VIDEO,

392 .priv_data_size = sizeof(PAFVideoDecContext),

393 .init = paf_video_init,

394 .close = paf_video_close,

395 .decode = paf_video_decode,

396 .capabilities = CODEC_CAP_DR1,

397 };

Generated on Sun Sep 14 2014 18:56:01 for FFmpeg by doxygen 1.8.2