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 "internal.h" 30 31typedef struct QpegContext{ 32 AVCodecContext *avctx; 33 AVFrame *pic, *ref; 34 uint32_t pal[256]; 35 GetByteContext buffer; 36} QpegContext; 37 38static void qpeg_decode_intra(QpegContext *qctx, uint8_t *dst, 39 int stride, int width, int height) 40{ 41 int i; 42 int code; 43 int c0, c1; 44 int run, copy; 45 int filled = 0; 46 int rows_to_go; 47 48 rows_to_go = height; 49 height--; 50 dst = dst + height * stride; 51 52 while ((bytestream2_get_bytes_left(&qctx->buffer) > 0) && (rows_to_go > 0)) { 53 code = bytestream2_get_byte(&qctx->buffer); 54 run = copy = 0; 55 if(code == 0xFC) /* end-of-picture code */ 56 break; 57 if(code >= 0xF8) { /* very long run */ 58 c0 = bytestream2_get_byte(&qctx->buffer); 59 c1 = bytestream2_get_byte(&qctx->buffer); 60 run = ((code & 0x7) << 16) + (c0 << 8) + c1 + 2; 61 } else if (code >= 0xF0) { /* long run */ 62 c0 = bytestream2_get_byte(&qctx->buffer); 63 run = ((code & 0xF) << 8) + c0 + 2; 64 } else if (code >= 0xE0) { /* short run */ 65 run = (code & 0x1F) + 2; 66 } else if (code >= 0xC0) { /* very long copy */ 67 c0 = bytestream2_get_byte(&qctx->buffer); 68 c1 = bytestream2_get_byte(&qctx->buffer); 69 copy = ((code & 0x3F) << 16) + (c0 << 8) + c1 + 1; 70 } else if (code >= 0x80) { /* long copy */ 71 c0 = bytestream2_get_byte(&qctx->buffer); 72 copy = ((code & 0x7F) << 8) + c0 + 1; 73 } else { /* short copy */ 74 copy = code + 1; 75 } 76 77 /* perform actual run or copy */ 78 if(run) { 79 int p; 80 81 p = bytestream2_get_byte(&qctx->buffer); 82 for(i = 0; i < run; i++) { 83 dst[filled++] = p; 84 if (filled >= width) { 85 filled = 0; 86 dst -= stride; 87 rows_to_go--; 88 if(rows_to_go <= 0) 89 break; 90 } 91 } 92 } else { 93 for(i = 0; i < copy; i++) { 94 dst[filled++] = bytestream2_get_byte(&qctx->buffer); 95 if (filled >= width) { 96 filled = 0; 97 dst -= stride; 98 rows_to_go--; 99 if(rows_to_go <= 0) 100 break; 101 } 102 } 103 } 104 } 105} 106 107static const int qpeg_table_h[16] = 108 { 0x00, 0x20, 0x20, 0x20, 0x18, 0x10, 0x10, 0x20, 0x10, 0x08, 0x18, 0x08, 0x08, 0x18, 0x10, 0x04}; 109static const int qpeg_table_w[16] = 110 { 0x00, 0x20, 0x18, 0x08, 0x18, 0x10, 0x20, 0x10, 0x08, 0x10, 0x20, 0x20, 0x08, 0x10, 0x18, 0x04}; 111 112/* Decodes delta frames */ 113static void av_noinline qpeg_decode_inter(QpegContext *qctx, uint8_t *dst, 114 int stride, int width, int height, 115 int delta, const uint8_t *ctable, 116 uint8_t *refdata) 117{ 118 int i, j; 119 int code; 120 int filled = 0; 121 int orig_height; 122 123 if(!refdata) 124 refdata= dst; 125 126 /* copy prev frame */ 127 for(i = 0; i < height; i++) 128 memcpy(dst + (i * stride), refdata + (i * stride), width); 129 130 orig_height = height; 131 height--; 132 dst = dst + height * stride; 133 134 while ((bytestream2_get_bytes_left(&qctx->buffer) > 0) && (height >= 0)) { 135 code = bytestream2_get_byte(&qctx->buffer); 136 137 if(delta) { 138 /* motion compensation */ 139 while(bytestream2_get_bytes_left(&qctx->buffer) > 0 && (code & 0xF0) == 0xF0) { 140 if(delta == 1) { 141 int me_idx; 142 int me_w, me_h, me_x, me_y; 143 uint8_t *me_plane; 144 int corr, val; 145 146 /* get block size by index */ 147 me_idx = code & 0xF; 148 me_w = qpeg_table_w[me_idx]; 149 me_h = qpeg_table_h[me_idx]; 150 151 /* extract motion vector */ 152 corr = bytestream2_get_byte(&qctx->buffer); 153 154 val = corr >> 4; 155 if(val > 7) 156 val -= 16; 157 me_x = val; 158 159 val = corr & 0xF; 160 if(val > 7) 161 val -= 16; 162 me_y = val; 163 164 /* check motion vector */ 165 if ((me_x + filled < 0) || (me_x + me_w + filled > width) || 166 (height - me_y - me_h < 0) || (height - me_y > orig_height) || 167 (filled + me_w > width) || (height - me_h < 0)) 168 av_log(NULL, AV_LOG_ERROR, "Bogus motion vector (%i,%i), block size %ix%i at %i,%i\n", 169 me_x, me_y, me_w, me_h, filled, height); 170 else { 171 /* do motion compensation */ 172 me_plane = refdata + (filled + me_x) + (height - me_y) * stride; 173 for(j = 0; j < me_h; j++) { 174 for(i = 0; i < me_w; i++) 175 dst[filled + i - (j * stride)] = me_plane[i - (j * stride)]; 176 } 177 } 178 } 179 code = bytestream2_get_byte(&qctx->buffer); 180 } 181 } 182 183 if(code == 0xE0) /* end-of-picture code */ 184 break; 185 if(code > 0xE0) { /* run code: 0xE1..0xFF */ 186 int p; 187 188 code &= 0x1F; 189 p = bytestream2_get_byte(&qctx->buffer); 190 for(i = 0; i <= code; i++) { 191 dst[filled++] = p; 192 if(filled >= width) { 193 filled = 0; 194 dst -= stride; 195 height--; 196 if (height < 0) 197 break; 198 } 199 } 200 } else if(code >= 0xC0) { /* copy code: 0xC0..0xDF */ 201 code &= 0x1F; 202 203 if(code + 1 > bytestream2_get_bytes_left(&qctx->buffer)) 204 break; 205 206 for(i = 0; i <= code; i++) { 207 dst[filled++] = bytestream2_get_byte(&qctx->buffer); 208 if(filled >= width) { 209 filled = 0; 210 dst -= stride; 211 height--; 212 if (height < 0) 213 break; 214 } 215 } 216 } else if(code >= 0x80) { /* skip code: 0x80..0xBF */ 217 int skip; 218 219 code &= 0x3F; 220 /* codes 0x80 and 0x81 are actually escape codes, 221 skip value minus constant is in the next byte */ 222 if(!code) 223 skip = bytestream2_get_byte(&qctx->buffer) + 64; 224 else if(code == 1) 225 skip = bytestream2_get_byte(&qctx->buffer) + 320; 226 else 227 skip = code; 228 filled += skip; 229 while( filled >= width) { 230 filled -= width; 231 dst -= stride; 232 height--; 233 if(height < 0) 234 break; 235 } 236 } else { 237 /* zero code treated as one-pixel skip */ 238 if(code) { 239 dst[filled++] = ctable[code & 0x7F]; 240 } 241 else 242 filled++; 243 if(filled >= width) { 244 filled = 0; 245 dst -= stride; 246 height--; 247 } 248 } 249 } 250} 251 252static int decode_frame(AVCodecContext *avctx, 253 void *data, int *got_frame, 254 AVPacket *avpkt) 255{ 256 uint8_t ctable[128]; 257 QpegContext * const a = avctx->priv_data; 258 AVFrame * const p = a->pic; 259 AVFrame * const ref = a->ref; 260 uint8_t* outdata; 261 int delta, ret; 262 const uint8_t *pal = av_packet_get_side_data(avpkt, AV_PKT_DATA_PALETTE, NULL); 263 264 if (avpkt->size < 0x86) { 265 av_log(avctx, AV_LOG_ERROR, "Packet is too small\n"); 266 return AVERROR_INVALIDDATA; 267 } 268 269 bytestream2_init(&a->buffer, avpkt->data, avpkt->size); 270 271 av_frame_unref(ref); 272 av_frame_move_ref(ref, p); 273 274 if ((ret = ff_get_buffer(avctx, p, AV_GET_BUFFER_FLAG_REF)) < 0) 275 return ret; 276 outdata = p->data[0]; 277 bytestream2_skip(&a->buffer, 4); 278 bytestream2_get_buffer(&a->buffer, ctable, 128); 279 bytestream2_skip(&a->buffer, 1); 280 281 delta = bytestream2_get_byte(&a->buffer); 282 if(delta == 0x10) { 283 qpeg_decode_intra(a, outdata, p->linesize[0], avctx->width, avctx->height); 284 } else { 285 qpeg_decode_inter(a, outdata, p->linesize[0], avctx->width, avctx->height, delta, ctable, ref->data[0]); 286 } 287 288 /* make the palette available on the way out */ 289 if (pal) { 290 p->palette_has_changed = 1; 291 memcpy(a->pal, pal, AVPALETTE_SIZE); 292 } 293 memcpy(p->data[1], a->pal, AVPALETTE_SIZE); 294 295 if ((ret = av_frame_ref(data, p)) < 0) 296 return ret; 297 298 *got_frame = 1; 299 300 return avpkt->size; 301} 302 303static void decode_flush(AVCodecContext *avctx){ 304 QpegContext * const a = avctx->priv_data; 305 int i, pal_size; 306 const uint8_t *pal_src; 307 308 pal_size = FFMIN(1024U, avctx->extradata_size); 309 pal_src = avctx->extradata + avctx->extradata_size - pal_size; 310 311 for (i=0; i<pal_size/4; i++) 312 a->pal[i] = 0xFFU<<24 | AV_RL32(pal_src+4*i); 313} 314 315static av_cold int decode_end(AVCodecContext *avctx) 316{ 317 QpegContext * const a = avctx->priv_data; 318 319 av_frame_free(&a->pic); 320 av_frame_free(&a->ref); 321 322 return 0; 323} 324 325static av_cold int decode_init(AVCodecContext *avctx){ 326 QpegContext * const a = avctx->priv_data; 327 328 a->avctx = avctx; 329 avctx->pix_fmt= AV_PIX_FMT_PAL8; 330 331 decode_flush(avctx); 332 333 a->pic = av_frame_alloc(); 334 a->ref = av_frame_alloc(); 335 if (!a->pic || !a->ref) { 336 decode_end(avctx); 337 return AVERROR(ENOMEM); 338 } 339 340 return 0; 341} 342 343AVCodec ff_qpeg_decoder = { 344 .name = "qpeg", 345 .long_name = NULL_IF_CONFIG_SMALL("Q-team QPEG"), 346 .type = AVMEDIA_TYPE_VIDEO, 347 .id = AV_CODEC_ID_QPEG, 348 .priv_data_size = sizeof(QpegContext), 349 .init = decode_init, 350 .close = decode_end, 351 .decode = decode_frame, 352 .flush = decode_flush, 353 .capabilities = CODEC_CAP_DR1, 354}; 355