FFmpeg: libavcodec/ulti.c Source File

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libavcodec

ulti.c

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1 /*

2 * IBM Ultimotion 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 /**

23 * @file

24 * IBM Ultimotion Video Decoder.

25 */

27 #include <stdio.h>

28 #include <stdlib.h>

29 #include <string.h>

31 #include "avcodec.h"

32 #include "bytestream.h"

33 #include "internal.h"

35 #include "ulti_cb.h"

37 typedef struct UltimotionDecodeContext {

38 AVCodecContext *avctx;

39 int width, height, blocks;

40 AVFrame *frame;

41 const uint8_t *ulti_codebook;

42 GetByteContext gb;

43 } UltimotionDecodeContext;

45 static av_cold int ulti_decode_init(AVCodecContext *avctx)

46 {

47 UltimotionDecodeContext *s = avctx->priv_data;

49 s->avctx = avctx;

50 s->width = avctx->width;

51 s->height = avctx->height;

52 s->blocks = (s->width / 8) * (s->height / 8);

53 avctx->pix_fmt = AV_PIX_FMT_YUV410P;

54 s->ulti_codebook = ulti_codebook;

56 s->frame = av_frame_alloc();

57 if (!s->frame)

58 return AVERROR(ENOMEM);

60 return 0;

61 }

63 static av_cold int ulti_decode_end(AVCodecContext *avctx){

64 UltimotionDecodeContext *s = avctx->priv_data;

66 av_frame_free(&s->frame);

68 return 0;

69 }

71 static const int block_coords[8] = // 4x4 block coords in 8x8 superblock

72 { 0, 0, 0, 4, 4, 4, 4, 0};

74 static const int angle_by_index[4] = { 0, 2, 6, 12};

76 /* Lookup tables for luma and chroma - used by ulti_convert_yuv() */

77 static const uint8_t ulti_lumas[64] =

78 { 0x10, 0x13, 0x17, 0x1A, 0x1E, 0x21, 0x25, 0x28,

79 0x2C, 0x2F, 0x33, 0x36, 0x3A, 0x3D, 0x41, 0x44,

80 0x48, 0x4B, 0x4F, 0x52, 0x56, 0x59, 0x5C, 0x60,

81 0x63, 0x67, 0x6A, 0x6E, 0x71, 0x75, 0x78, 0x7C,

82 0x7F, 0x83, 0x86, 0x8A, 0x8D, 0x91, 0x94, 0x98,

83 0x9B, 0x9F, 0xA2, 0xA5, 0xA9, 0xAC, 0xB0, 0xB3,

84 0xB7, 0xBA, 0xBE, 0xC1, 0xC5, 0xC8, 0xCC, 0xCF,

85 0xD3, 0xD6, 0xDA, 0xDD, 0xE1, 0xE4, 0xE8, 0xEB};

87 static const uint8_t ulti_chromas[16] =

88 { 0x60, 0x67, 0x6D, 0x73, 0x7A, 0x80, 0x86, 0x8D,

89 0x93, 0x99, 0xA0, 0xA6, 0xAC, 0xB3, 0xB9, 0xC0};

91 /* convert Ultimotion YUV block (sixteen 6-bit Y samples and

92 two 4-bit chroma samples) into standard YUV and put it into frame */

93 static void ulti_convert_yuv(AVFrame *frame, int x, int y,

94 uint8_t *luma,int chroma)

95 {

96 uint8_t *y_plane, *cr_plane, *cb_plane;

97 int i;

99 y_plane = frame->data[0] + x + y * frame->linesize[0];

100 cr_plane = frame->data[1] + (x / 4) + (y / 4) * frame->linesize[1];

101 cb_plane = frame->data[2] + (x / 4) + (y / 4) * frame->linesize[2];

102

103 cr_plane[0] = ulti_chromas[chroma >> 4];

104

105 cb_plane[0] = ulti_chromas[chroma & 0xF];

106

107

108 for(i = 0; i < 16; i++){

109 y_plane[i & 3] = ulti_lumas[luma[i]];

110 if((i & 3) == 3) { //next row

111 y_plane += frame->linesize[0];

112 }

113 }

114 }

115

116 /* generate block like in MS Video1 */

117 static void ulti_pattern(AVFrame *frame, int x, int y,

118 int f0, int f1, int Y0, int Y1, int chroma)

119 {

120 uint8_t Luma[16];

121 int mask, i;

122 for(mask = 0x80, i = 0; mask; mask >>= 1, i++) {

123 if(f0 & mask)

124 Luma[i] = Y1;

125 else

126 Luma[i] = Y0;

127 }

128

129 for(mask = 0x80, i = 8; mask; mask >>= 1, i++) {

130 if(f1 & mask)

131 Luma[i] = Y1;

132 else

133 Luma[i] = Y0;

134 }

135

136 ulti_convert_yuv(frame, x, y, Luma, chroma);

137 }

138

139 /* fill block with some gradient */

140 static void ulti_grad(AVFrame *frame, int x, int y, uint8_t *Y, int chroma, int angle)

141 {

142 uint8_t Luma[16];

143 if(angle & 8) { //reverse order

144 int t;

145 angle &= 0x7;

146 t = Y[0];

147 Y[0] = Y[3];

148 Y[3] = t;

149 t = Y[1];

150 Y[1] = Y[2];

151 Y[2] = t;

152 }

153 switch(angle){

154 case 0:

155 Luma[0] = Y[0]; Luma[1] = Y[1]; Luma[2] = Y[2]; Luma[3] = Y[3];

156 Luma[4] = Y[0]; Luma[5] = Y[1]; Luma[6] = Y[2]; Luma[7] = Y[3];

157 Luma[8] = Y[0]; Luma[9] = Y[1]; Luma[10] = Y[2]; Luma[11] = Y[3];

158 Luma[12] = Y[0]; Luma[13] = Y[1]; Luma[14] = Y[2]; Luma[15] = Y[3];

159 break;

160 case 1:

161 Luma[0] = Y[1]; Luma[1] = Y[2]; Luma[2] = Y[3]; Luma[3] = Y[3];

162 Luma[4] = Y[0]; Luma[5] = Y[1]; Luma[6] = Y[2]; Luma[7] = Y[3];

163 Luma[8] = Y[0]; Luma[9] = Y[1]; Luma[10] = Y[2]; Luma[11] = Y[3];

164 Luma[12] = Y[0]; Luma[13] = Y[0]; Luma[14] = Y[1]; Luma[15] = Y[2];

165 break;

166 case 2:

167 Luma[0] = Y[1]; Luma[1] = Y[2]; Luma[2] = Y[3]; Luma[3] = Y[3];

168 Luma[4] = Y[1]; Luma[5] = Y[2]; Luma[6] = Y[2]; Luma[7] = Y[3];

169 Luma[8] = Y[0]; Luma[9] = Y[1]; Luma[10] = Y[1]; Luma[11] = Y[2];

170 Luma[12] = Y[0]; Luma[13] = Y[0]; Luma[14] = Y[1]; Luma[15] = Y[2];

171 break;

172 case 3:

173 Luma[0] = Y[2]; Luma[1] = Y[3]; Luma[2] = Y[3]; Luma[3] = Y[3];

174 Luma[4] = Y[1]; Luma[5] = Y[2]; Luma[6] = Y[2]; Luma[7] = Y[3];

175 Luma[8] = Y[0]; Luma[9] = Y[1]; Luma[10] = Y[1]; Luma[11] = Y[2];

176 Luma[12] = Y[0]; Luma[13] = Y[0]; Luma[14] = Y[0]; Luma[15] = Y[1];

177 break;

178 case 4:

179 Luma[0] = Y[3]; Luma[1] = Y[3]; Luma[2] = Y[3]; Luma[3] = Y[3];

180 Luma[4] = Y[2]; Luma[5] = Y[2]; Luma[6] = Y[2]; Luma[7] = Y[2];

181 Luma[8] = Y[1]; Luma[9] = Y[1]; Luma[10] = Y[1]; Luma[11] = Y[1];

182 Luma[12] = Y[0]; Luma[13] = Y[0]; Luma[14] = Y[0]; Luma[15] = Y[0];

183 break;

184 case 5:

185 Luma[0] = Y[3]; Luma[1] = Y[3]; Luma[2] = Y[3]; Luma[3] = Y[2];

186 Luma[4] = Y[3]; Luma[5] = Y[2]; Luma[6] = Y[2]; Luma[7] = Y[1];

187 Luma[8] = Y[2]; Luma[9] = Y[1]; Luma[10] = Y[1]; Luma[11] = Y[0];

188 Luma[12] = Y[1]; Luma[13] = Y[0]; Luma[14] = Y[0]; Luma[15] = Y[0];

189 break;

190 case 6:

191 Luma[0] = Y[3]; Luma[1] = Y[3]; Luma[2] = Y[2]; Luma[3] = Y[2];

192 Luma[4] = Y[3]; Luma[5] = Y[2]; Luma[6] = Y[1]; Luma[7] = Y[1];

193 Luma[8] = Y[2]; Luma[9] = Y[2]; Luma[10] = Y[1]; Luma[11] = Y[0];

194 Luma[12] = Y[1]; Luma[13] = Y[1]; Luma[14] = Y[0]; Luma[15] = Y[0];

195 break;

196 case 7:

197 Luma[0] = Y[3]; Luma[1] = Y[3]; Luma[2] = Y[2]; Luma[3] = Y[1];

198 Luma[4] = Y[3]; Luma[5] = Y[2]; Luma[6] = Y[1]; Luma[7] = Y[0];

199 Luma[8] = Y[3]; Luma[9] = Y[2]; Luma[10] = Y[1]; Luma[11] = Y[0];

200 Luma[12] = Y[2]; Luma[13] = Y[1]; Luma[14] = Y[0]; Luma[15] = Y[0];

201 break;

202 default:

203 Luma[0] = Y[0]; Luma[1] = Y[0]; Luma[2] = Y[1]; Luma[3] = Y[1];

204 Luma[4] = Y[0]; Luma[5] = Y[0]; Luma[6] = Y[1]; Luma[7] = Y[1];

205 Luma[8] = Y[2]; Luma[9] = Y[2]; Luma[10] = Y[3]; Luma[11] = Y[3];

206 Luma[12] = Y[2]; Luma[13] = Y[2]; Luma[14] = Y[3]; Luma[15] = Y[3];

207 break;

208 }

209

210 ulti_convert_yuv(frame, x, y, Luma, chroma);

211 }

212

213 static int ulti_decode_frame(AVCodecContext *avctx,

214 void *data, int *got_frame,

215 AVPacket *avpkt)

216 {

217 const uint8_t *buf = avpkt->data;

218 int buf_size = avpkt->size;

219 UltimotionDecodeContext *s=avctx->priv_data;

220 int modifier = 0;

221 int uniq = 0;

222 int mode = 0;

223 int blocks = 0;

224 int done = 0;

225 int x = 0, y = 0;

226 int i, ret;

227 int skip;

228 int tmp;

229

230 if ((ret = ff_reget_buffer(avctx, s->frame)) < 0)

231 return ret;

232

233 bytestream2_init(&s->gb, buf, buf_size);

234

235 while(!done) {

236 int idx;

237 if(blocks >= s->blocks || y >= s->height)

238 break;//all blocks decoded

239

240 if (bytestream2_get_bytes_left(&s->gb) < 1)

241 goto err;

242 idx = bytestream2_get_byteu(&s->gb);

243 if((idx & 0xF8) == 0x70) {

244 switch(idx) {

245 case 0x70: //change modifier

246 modifier = bytestream2_get_byte(&s->gb);

247 if(modifier>1)

248 av_log(avctx, AV_LOG_INFO, "warning: modifier must be 0 or 1, got %i\n", modifier);

249 break;

250 case 0x71: // set uniq flag

251 uniq = 1;

252 break;

253 case 0x72: //toggle mode

254 mode = !mode;

255 break;

256 case 0x73: //end-of-frame

257 done = 1;

258 break;

259 case 0x74: //skip some blocks

260 skip = bytestream2_get_byte(&s->gb);

261 if ((blocks + skip) >= s->blocks)

262 break;

263 blocks += skip;

264 x += skip * 8;

265 while(x >= s->width) {

266 x -= s->width;

267 y += 8;

268 }

269 break;

270 default:

271 av_log(avctx, AV_LOG_INFO, "warning: unknown escape 0x%02X\n", idx);

272 }

273 } else { //handle one block

274 int code;

275 int cf;

276 int angle = 0;

277 uint8_t Y[4]; // luma samples of block

278 int tx = 0, ty = 0; //coords of subblock

279 int chroma = 0;

280 if (mode || uniq) {

281 uniq = 0;

282 cf = 1;

283 chroma = 0;

284 } else {

285 cf = 0;

286 if (idx) {

287 chroma = bytestream2_get_byte(&s->gb);

288 }

289 }

290 for (i = 0; i < 4; i++) { // for every subblock

291 code = (idx >> (6 - i*2)) & 3; //extract 2 bits

292 if(!code) //skip subblock

293 continue;

294 if(cf) {

295 chroma = bytestream2_get_byte(&s->gb);

296 }

297 tx = x + block_coords[i * 2];

298 ty = y + block_coords[(i * 2) + 1];

299 switch(code) {

300 case 1:

301 tmp = bytestream2_get_byte(&s->gb);

302

303 angle = angle_by_index[(tmp >> 6) & 0x3];

304

305 Y[0] = tmp & 0x3F;

306 Y[1] = Y[0];

307

308 if (angle) {

309 Y[2] = Y[0]+1;

310 if (Y[2] > 0x3F)

311 Y[2] = 0x3F;

312 Y[3] = Y[2];

313 } else {

314 Y[2] = Y[0];

315 Y[3] = Y[0];

316 }

317 break;

318

319 case 2:

320 if (modifier) { // unpack four luma samples

321 tmp = bytestream2_get_be24(&s->gb);

322

323 Y[0] = (tmp >> 18) & 0x3F;

324 Y[1] = (tmp >> 12) & 0x3F;

325 Y[2] = (tmp >> 6) & 0x3F;

326 Y[3] = tmp & 0x3F;

327 angle = 16;

328 } else { // retrieve luma samples from codebook

329 tmp = bytestream2_get_be16(&s->gb);

330

331 angle = (tmp >> 12) & 0xF;

332 tmp &= 0xFFF;

333 tmp <<= 2;

334 Y[0] = s->ulti_codebook[tmp];

335 Y[1] = s->ulti_codebook[tmp + 1];

336 Y[2] = s->ulti_codebook[tmp + 2];

337 Y[3] = s->ulti_codebook[tmp + 3];

338 }

339 break;

340

341 case 3:

342 if (modifier) { // all 16 luma samples

343 uint8_t Luma[16];

344

345 if (bytestream2_get_bytes_left(&s->gb) < 12)

346 goto err;

347 tmp = bytestream2_get_be24u(&s->gb);

348 Luma[0] = (tmp >> 18) & 0x3F;

349 Luma[1] = (tmp >> 12) & 0x3F;

350 Luma[2] = (tmp >> 6) & 0x3F;

351 Luma[3] = tmp & 0x3F;

352

353 tmp = bytestream2_get_be24u(&s->gb);

354 Luma[4] = (tmp >> 18) & 0x3F;

355 Luma[5] = (tmp >> 12) & 0x3F;

356 Luma[6] = (tmp >> 6) & 0x3F;

357 Luma[7] = tmp & 0x3F;

358

359 tmp = bytestream2_get_be24u(&s->gb);

360 Luma[8] = (tmp >> 18) & 0x3F;

361 Luma[9] = (tmp >> 12) & 0x3F;

362 Luma[10] = (tmp >> 6) & 0x3F;

363 Luma[11] = tmp & 0x3F;

364

365 tmp = bytestream2_get_be24u(&s->gb);

366 Luma[12] = (tmp >> 18) & 0x3F;

367 Luma[13] = (tmp >> 12) & 0x3F;

368 Luma[14] = (tmp >> 6) & 0x3F;

369 Luma[15] = tmp & 0x3F;

370

371 ulti_convert_yuv(s->frame, tx, ty, Luma, chroma);

372 } else {

373 if (bytestream2_get_bytes_left(&s->gb) < 4)

374 goto err;

375 tmp = bytestream2_get_byteu(&s->gb);

376 if(tmp & 0x80) {

377 angle = (tmp >> 4) & 0x7;

378 tmp = (tmp << 8) + bytestream2_get_byteu(&s->gb);

379 Y[0] = (tmp >> 6) & 0x3F;

380 Y[1] = tmp & 0x3F;

381 Y[2] = bytestream2_get_byteu(&s->gb) & 0x3F;

382 Y[3] = bytestream2_get_byteu(&s->gb) & 0x3F;

383 ulti_grad(s->frame, tx, ty, Y, chroma, angle); //draw block

384 } else { // some patterns

385 int f0, f1;

386 f0 = bytestream2_get_byteu(&s->gb);

387 f1 = tmp;

388 Y[0] = bytestream2_get_byteu(&s->gb) & 0x3F;

389 Y[1] = bytestream2_get_byteu(&s->gb) & 0x3F;

390 ulti_pattern(s->frame, tx, ty, f1, f0, Y[0], Y[1], chroma);

391 }

392 }

393 break;

394 }

395 if(code != 3)

396 ulti_grad(s->frame, tx, ty, Y, chroma, angle); // draw block

397 }

398 blocks++;

399 x += 8;

400 if(x >= s->width) {

401 x = 0;

402 y += 8;

403 }

404 }

405 }

406

407 *got_frame = 1;

408 if ((ret = av_frame_ref(data, s->frame)) < 0)

409 return ret;

410

411 return buf_size;

412

413 err:

414 av_log(avctx, AV_LOG_ERROR,

415 "Insufficient data\n");

416 return AVERROR_INVALIDDATA;

417 }

418

419 AVCodec ff_ulti_decoder = {

420 .name = "ultimotion",

421 .long_name = NULL_IF_CONFIG_SMALL("IBM UltiMotion"),

422 .type = AVMEDIA_TYPE_VIDEO,

423 .id = AV_CODEC_ID_ULTI,

424 .priv_data_size = sizeof(UltimotionDecodeContext),

425 .init = ulti_decode_init,

426 .close = ulti_decode_end,

427 .decode = ulti_decode_frame,

428 .capabilities = CODEC_CAP_DR1,

429 };

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