1/* 2 * QPEG codec 3 * Copyright (c) 2004 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 * QPEG codec. 25 */ 26 27#include "avcodec.h" 28#include "bytestream.h" 29#include "codec_internal.h" 30#include "decode.h" 31#include "internal.h" 32 33typedef struct QpegContext{ 34 AVCodecContext *avctx; 35 AVFrame *ref; 36 uint32_t pal[256]; 37 GetByteContext buffer; 38} QpegContext; 39 40static void qpeg_decode_intra(QpegContext *qctx, uint8_t *dst, 41 int stride, int width, int height) 42{ 43 int i; 44 int code; 45 int c0, c1; 46 int run, copy; 47 int filled = 0; 48 int rows_to_go; 49 50 rows_to_go = height; 51 height--; 52 dst = dst + height * stride; 53 54 while ((bytestream2_get_bytes_left(&qctx->buffer) > 0) && (rows_to_go > 0)) { 55 code = bytestream2_get_byte(&qctx->buffer); 56 run = copy = 0; 57 if(code == 0xFC) /* end-of-picture code */ 58 break; 59 if(code >= 0xF8) { /* very long run */ 60 c0 = bytestream2_get_byte(&qctx->buffer); 61 c1 = bytestream2_get_byte(&qctx->buffer); 62 run = ((code & 0x7) << 16) + (c0 << 8) + c1 + 2; 63 } else if (code >= 0xF0) { /* long run */ 64 c0 = bytestream2_get_byte(&qctx->buffer); 65 run = ((code & 0xF) << 8) + c0 + 2; 66 } else if (code >= 0xE0) { /* short run */ 67 run = (code & 0x1F) + 2; 68 } else if (code >= 0xC0) { /* very long copy */ 69 c0 = bytestream2_get_byte(&qctx->buffer); 70 c1 = bytestream2_get_byte(&qctx->buffer); 71 copy = ((code & 0x3F) << 16) + (c0 << 8) + c1 + 1; 72 } else if (code >= 0x80) { /* long copy */ 73 c0 = bytestream2_get_byte(&qctx->buffer); 74 copy = ((code & 0x7F) << 8) + c0 + 1; 75 } else { /* short copy */ 76 copy = code + 1; 77 } 78 79 /* perform actual run or copy */ 80 if(run) { 81 int p; 82 83 p = bytestream2_get_byte(&qctx->buffer); 84 for(i = 0; i < run; i++) { 85 int step = FFMIN(run - i, width - filled); 86 memset(dst+filled, p, step); 87 filled += step; 88 i += step - 1; 89 if (filled >= width) { 90 filled = 0; 91 dst -= stride; 92 rows_to_go--; 93 while (run - i > width && rows_to_go > 0) { 94 memset(dst, p, width); 95 dst -= stride; 96 rows_to_go--; 97 i += width; 98 } 99 if(rows_to_go <= 0) 100 break; 101 } 102 } 103 } else { 104 if (bytestream2_get_bytes_left(&qctx->buffer) < copy) 105 copy = bytestream2_get_bytes_left(&qctx->buffer); 106 while (copy > 0) { 107 int step = FFMIN(copy, width - filled); 108 bytestream2_get_bufferu(&qctx->buffer, dst + filled, step); 109 filled += step; 110 copy -= step; 111 if (filled >= width) { 112 filled = 0; 113 dst -= stride; 114 rows_to_go--; 115 if(rows_to_go <= 0) 116 break; 117 } 118 } 119 } 120 } 121} 122 123static const uint8_t qpeg_table_h[16] = 124 { 0x00, 0x20, 0x20, 0x20, 0x18, 0x10, 0x10, 0x20, 0x10, 0x08, 0x18, 0x08, 0x08, 0x18, 0x10, 0x04}; 125static const uint8_t qpeg_table_w[16] = 126 { 0x00, 0x20, 0x18, 0x08, 0x18, 0x10, 0x20, 0x10, 0x08, 0x10, 0x20, 0x20, 0x08, 0x10, 0x18, 0x04}; 127 128/* Decodes delta frames */ 129static void av_noinline qpeg_decode_inter(QpegContext *qctx, uint8_t *dst, 130 int stride, int width, int height, 131 int delta, const uint8_t *ctable, 132 uint8_t *refdata) 133{ 134 int i, j; 135 int code; 136 int filled = 0; 137 int orig_height; 138 139 if (refdata) { 140 /* copy prev frame */ 141 for (i = 0; i < height; i++) 142 memcpy(dst + (i * stride), refdata + (i * stride), width); 143 } else { 144 refdata = dst; 145 } 146 147 orig_height = height; 148 height--; 149 dst = dst + height * stride; 150 151 while ((bytestream2_get_bytes_left(&qctx->buffer) > 0) && (height >= 0)) { 152 code = bytestream2_get_byte(&qctx->buffer); 153 154 if(delta) { 155 /* motion compensation */ 156 while(bytestream2_get_bytes_left(&qctx->buffer) > 0 && (code & 0xF0) == 0xF0) { 157 if(delta == 1) { 158 int me_idx; 159 int me_w, me_h, me_x, me_y; 160 uint8_t *me_plane; 161 int corr, val; 162 163 /* get block size by index */ 164 me_idx = code & 0xF; 165 me_w = qpeg_table_w[me_idx]; 166 me_h = qpeg_table_h[me_idx]; 167 168 /* extract motion vector */ 169 corr = bytestream2_get_byte(&qctx->buffer); 170 171 val = corr >> 4; 172 if(val > 7) 173 val -= 16; 174 me_x = val; 175 176 val = corr & 0xF; 177 if(val > 7) 178 val -= 16; 179 me_y = val; 180 181 /* check motion vector */ 182 if ((me_x + filled < 0) || (me_x + me_w + filled > width) || 183 (height - me_y - me_h < 0) || (height - me_y >= orig_height) || 184 (filled + me_w > width) || (height - me_h < 0)) 185 av_log(qctx->avctx, AV_LOG_ERROR, "Bogus motion vector (%i,%i), block size %ix%i at %i,%i\n", 186 me_x, me_y, me_w, me_h, filled, height); 187 else { 188 /* do motion compensation */ 189 me_plane = refdata + (filled + me_x) + (height - me_y) * stride; 190 for(j = 0; j < me_h; j++) { 191 for(i = 0; i < me_w; i++) 192 dst[filled + i - (j * stride)] = me_plane[i - (j * stride)]; 193 } 194 } 195 } 196 code = bytestream2_get_byte(&qctx->buffer); 197 } 198 } 199 200 if(code == 0xE0) /* end-of-picture code */ 201 break; 202 if(code > 0xE0) { /* run code: 0xE1..0xFF */ 203 int p; 204 205 code &= 0x1F; 206 p = bytestream2_get_byte(&qctx->buffer); 207 for(i = 0; i <= code; i++) { 208 dst[filled++] = p; 209 if(filled >= width) { 210 filled = 0; 211 dst -= stride; 212 height--; 213 if (height < 0) 214 break; 215 } 216 } 217 } else if(code >= 0xC0) { /* copy code: 0xC0..0xDF */ 218 code &= 0x1F; 219 220 if(code + 1 > bytestream2_get_bytes_left(&qctx->buffer)) 221 break; 222 223 for(i = 0; i <= code; i++) { 224 dst[filled++] = bytestream2_get_byte(&qctx->buffer); 225 if(filled >= width) { 226 filled = 0; 227 dst -= stride; 228 height--; 229 if (height < 0) 230 break; 231 } 232 } 233 } else if(code >= 0x80) { /* skip code: 0x80..0xBF */ 234 int skip; 235 236 code &= 0x3F; 237 /* codes 0x80 and 0x81 are actually escape codes, 238 skip value minus constant is in the next byte */ 239 if(!code) 240 skip = bytestream2_get_byte(&qctx->buffer) + 64; 241 else if(code == 1) 242 skip = bytestream2_get_byte(&qctx->buffer) + 320; 243 else 244 skip = code; 245 filled += skip; 246 while( filled >= width) { 247 filled -= width; 248 dst -= stride; 249 height--; 250 if(height < 0) 251 break; 252 } 253 } else { 254 /* zero code treated as one-pixel skip */ 255 if(code) { 256 dst[filled++] = ctable[code & 0x7F]; 257 } 258 else 259 filled++; 260 if(filled >= width) { 261 filled = 0; 262 dst -= stride; 263 height--; 264 } 265 } 266 } 267} 268 269static int decode_frame(AVCodecContext *avctx, AVFrame *p, 270 int *got_frame, AVPacket *avpkt) 271{ 272 uint8_t ctable[128]; 273 QpegContext * const a = avctx->priv_data; 274 AVFrame * const ref = a->ref; 275 uint8_t* outdata; 276 int delta, intra, ret; 277 278 if (avpkt->size < 0x86) { 279 av_log(avctx, AV_LOG_ERROR, "Packet is too small\n"); 280 return AVERROR_INVALIDDATA; 281 } 282 283 bytestream2_init(&a->buffer, avpkt->data, avpkt->size); 284 285 if ((ret = ff_get_buffer(avctx, p, AV_GET_BUFFER_FLAG_REF)) < 0) 286 return ret; 287 outdata = p->data[0]; 288 bytestream2_skip(&a->buffer, 4); 289 bytestream2_get_buffer(&a->buffer, ctable, 128); 290 bytestream2_skip(&a->buffer, 1); 291 292 delta = bytestream2_get_byte(&a->buffer); 293 intra = delta == 0x10; 294 if (intra) { 295 qpeg_decode_intra(a, outdata, p->linesize[0], avctx->width, avctx->height); 296 } else { 297 qpeg_decode_inter(a, outdata, p->linesize[0], avctx->width, avctx->height, delta, ctable, ref->data[0]); 298 } 299 300 /* make the palette available on the way out */ 301 p->palette_has_changed = ff_copy_palette(a->pal, avpkt, avctx); 302 memcpy(p->data[1], a->pal, AVPALETTE_SIZE); 303 304 av_frame_unref(ref); 305 if ((ret = av_frame_ref(ref, p)) < 0) 306 return ret; 307 308 p->key_frame = intra; 309 p->pict_type = intra ? AV_PICTURE_TYPE_I : AV_PICTURE_TYPE_P; 310 311 *got_frame = 1; 312 313 return avpkt->size; 314} 315 316static void decode_flush(AVCodecContext *avctx){ 317 QpegContext * const a = avctx->priv_data; 318 int i, pal_size; 319 const uint8_t *pal_src; 320 321 av_frame_unref(a->ref); 322 323 pal_size = FFMIN(1024U, avctx->extradata_size); 324 pal_src = avctx->extradata + avctx->extradata_size - pal_size; 325 326 for (i=0; i<pal_size/4; i++) 327 a->pal[i] = 0xFFU<<24 | AV_RL32(pal_src+4*i); 328} 329 330static av_cold int decode_end(AVCodecContext *avctx) 331{ 332 QpegContext * const a = avctx->priv_data; 333 334 av_frame_free(&a->ref); 335 336 return 0; 337} 338 339static av_cold int decode_init(AVCodecContext *avctx){ 340 QpegContext * const a = avctx->priv_data; 341 342 a->avctx = avctx; 343 avctx->pix_fmt= AV_PIX_FMT_PAL8; 344 345 a->ref = av_frame_alloc(); 346 if (!a->ref) 347 return AVERROR(ENOMEM); 348 349 decode_flush(avctx); 350 351 return 0; 352} 353 354const FFCodec ff_qpeg_decoder = { 355 .p.name = "qpeg", 356 .p.long_name = NULL_IF_CONFIG_SMALL("Q-team QPEG"), 357 .p.type = AVMEDIA_TYPE_VIDEO, 358 .p.id = AV_CODEC_ID_QPEG, 359 .priv_data_size = sizeof(QpegContext), 360 .init = decode_init, 361 .close = decode_end, 362 FF_CODEC_DECODE_CB(decode_frame), 363 .flush = decode_flush, 364 .p.capabilities = AV_CODEC_CAP_DR1, 365 .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE | 366 FF_CODEC_CAP_INIT_CLEANUP, 367}; 368