| 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 | |
| 31 | typedef struct QpegContext{ |
| 32 | AVCodecContext *avctx; |
| 33 | AVFrame *pic, *ref; |
| 34 | uint32_t pal[256]; |
| 35 | GetByteContext buffer; |
| 36 | } QpegContext; |
| 37 | |
| 38 | static 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 | |
| 107 | static const int qpeg_table_h[16] = |
| 108 | { 0x00, 0x20, 0x20, 0x20, 0x18, 0x10, 0x10, 0x20, 0x10, 0x08, 0x18, 0x08, 0x08, 0x18, 0x10, 0x04}; |
| 109 | static 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 */ |
| 113 | static 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 | |
| 252 | static 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 | |
| 303 | static 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 | |
| 315 | static 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 | |
| 325 | static 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 | |
| 343 | AVCodec 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 | }; |