| 1 | /* |
| 2 | * Quicktime Animation (RLE) Video Encoder |
| 3 | * Copyright (C) 2007 Clemens Fruhwirth |
| 4 | * Copyright (C) 2007 Alexis Ballier |
| 5 | * |
| 6 | * This file is based on flashsvenc.c. |
| 7 | * |
| 8 | * This file is part of FFmpeg. |
| 9 | * |
| 10 | * FFmpeg is free software; you can redistribute it and/or |
| 11 | * modify it under the terms of the GNU Lesser General Public |
| 12 | * License as published by the Free Software Foundation; either |
| 13 | * version 2.1 of the License, or (at your option) any later version. |
| 14 | * |
| 15 | * FFmpeg is distributed in the hope that it will be useful, |
| 16 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 17 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 18 | * Lesser General Public License for more details. |
| 19 | * |
| 20 | * You should have received a copy of the GNU Lesser General Public |
| 21 | * License along with FFmpeg; if not, write to the Free Software |
| 22 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| 23 | */ |
| 24 | |
| 25 | #include "libavutil/imgutils.h" |
| 26 | #include "avcodec.h" |
| 27 | #include "bytestream.h" |
| 28 | #include "internal.h" |
| 29 | |
| 30 | /** Maximum RLE code for bulk copy */ |
| 31 | #define MAX_RLE_BULK 127 |
| 32 | /** Maximum RLE code for repeat */ |
| 33 | #define MAX_RLE_REPEAT 128 |
| 34 | /** Maximum RLE code for skip */ |
| 35 | #define MAX_RLE_SKIP 254 |
| 36 | |
| 37 | typedef struct QtrleEncContext { |
| 38 | AVCodecContext *avctx; |
| 39 | int pixel_size; |
| 40 | AVPicture previous_frame; |
| 41 | unsigned int max_buf_size; |
| 42 | int logical_width; |
| 43 | /** |
| 44 | * This array will contain at ith position the value of the best RLE code |
| 45 | * if the line started at pixel i |
| 46 | * There can be 3 values : |
| 47 | * skip (0) : skip as much as possible pixels because they are equal to the |
| 48 | * previous frame ones |
| 49 | * repeat (<-1) : repeat that pixel -rle_code times, still as much as |
| 50 | * possible |
| 51 | * copy (>0) : copy the raw next rle_code pixels */ |
| 52 | signed char *rlecode_table; |
| 53 | /** |
| 54 | * This array will contain the length of the best rle encoding of the line |
| 55 | * starting at ith pixel */ |
| 56 | int *length_table; |
| 57 | /** |
| 58 | * Will contain at ith position the number of consecutive pixels equal to the previous |
| 59 | * frame starting from pixel i */ |
| 60 | uint8_t* skip_table; |
| 61 | } QtrleEncContext; |
| 62 | |
| 63 | static av_cold int qtrle_encode_end(AVCodecContext *avctx) |
| 64 | { |
| 65 | QtrleEncContext *s = avctx->priv_data; |
| 66 | |
| 67 | av_frame_free(&avctx->coded_frame); |
| 68 | |
| 69 | avpicture_free(&s->previous_frame); |
| 70 | av_free(s->rlecode_table); |
| 71 | av_free(s->length_table); |
| 72 | av_free(s->skip_table); |
| 73 | return 0; |
| 74 | } |
| 75 | |
| 76 | static av_cold int qtrle_encode_init(AVCodecContext *avctx) |
| 77 | { |
| 78 | QtrleEncContext *s = avctx->priv_data; |
| 79 | int ret; |
| 80 | |
| 81 | if (av_image_check_size(avctx->width, avctx->height, 0, avctx) < 0) { |
| 82 | return AVERROR(EINVAL); |
| 83 | } |
| 84 | s->avctx=avctx; |
| 85 | s->logical_width=avctx->width; |
| 86 | |
| 87 | switch (avctx->pix_fmt) { |
| 88 | case AV_PIX_FMT_GRAY8: |
| 89 | if (avctx->width % 4) { |
| 90 | av_log(avctx, AV_LOG_ERROR, "Width not being a multiple of 4 is not supported\n"); |
| 91 | return AVERROR(EINVAL); |
| 92 | } |
| 93 | s->logical_width = avctx->width / 4; |
| 94 | s->pixel_size = 4; |
| 95 | break; |
| 96 | case AV_PIX_FMT_RGB555BE: |
| 97 | s->pixel_size = 2; |
| 98 | break; |
| 99 | case AV_PIX_FMT_RGB24: |
| 100 | s->pixel_size = 3; |
| 101 | break; |
| 102 | case AV_PIX_FMT_ARGB: |
| 103 | s->pixel_size = 4; |
| 104 | break; |
| 105 | default: |
| 106 | av_log(avctx, AV_LOG_ERROR, "Unsupported colorspace.\n"); |
| 107 | break; |
| 108 | } |
| 109 | avctx->bits_per_coded_sample = avctx->pix_fmt == AV_PIX_FMT_GRAY8 ? 40 : s->pixel_size*8; |
| 110 | |
| 111 | s->rlecode_table = av_mallocz(s->logical_width); |
| 112 | s->skip_table = av_mallocz(s->logical_width); |
| 113 | s->length_table = av_mallocz_array(s->logical_width + 1, sizeof(int)); |
| 114 | if (!s->skip_table || !s->length_table || !s->rlecode_table) { |
| 115 | av_log(avctx, AV_LOG_ERROR, "Error allocating memory.\n"); |
| 116 | return AVERROR(ENOMEM); |
| 117 | } |
| 118 | if ((ret = avpicture_alloc(&s->previous_frame, avctx->pix_fmt, avctx->width, avctx->height)) < 0) { |
| 119 | av_log(avctx, AV_LOG_ERROR, "Error allocating picture\n"); |
| 120 | return ret; |
| 121 | } |
| 122 | |
| 123 | s->max_buf_size = s->logical_width*s->avctx->height*s->pixel_size*2 /* image base material */ |
| 124 | + 15 /* header + footer */ |
| 125 | + s->avctx->height*2 /* skip code+rle end */ |
| 126 | + s->logical_width/MAX_RLE_BULK + 1 /* rle codes */; |
| 127 | |
| 128 | avctx->coded_frame = av_frame_alloc(); |
| 129 | if (!avctx->coded_frame) { |
| 130 | qtrle_encode_end(avctx); |
| 131 | return AVERROR(ENOMEM); |
| 132 | } |
| 133 | |
| 134 | return 0; |
| 135 | } |
| 136 | |
| 137 | /** |
| 138 | * Compute the best RLE sequence for a line |
| 139 | */ |
| 140 | static void qtrle_encode_line(QtrleEncContext *s, const AVFrame *p, int line, uint8_t **buf) |
| 141 | { |
| 142 | int width=s->logical_width; |
| 143 | int i; |
| 144 | signed char rlecode; |
| 145 | |
| 146 | /* This will be the number of pixels equal to the preivous frame one's |
| 147 | * starting from the ith pixel */ |
| 148 | unsigned int skipcount; |
| 149 | /* This will be the number of consecutive equal pixels in the current |
| 150 | * frame, starting from the ith one also */ |
| 151 | unsigned int av_uninit(repeatcount); |
| 152 | |
| 153 | /* The cost of the three different possibilities */ |
| 154 | int total_skip_cost; |
| 155 | int total_repeat_cost; |
| 156 | |
| 157 | int base_bulk_cost; |
| 158 | int lowest_bulk_cost; |
| 159 | int lowest_bulk_cost_index; |
| 160 | int sec_lowest_bulk_cost; |
| 161 | int sec_lowest_bulk_cost_index; |
| 162 | |
| 163 | uint8_t *this_line = p-> data[0] + line*p-> linesize[0] + |
| 164 | (width - 1)*s->pixel_size; |
| 165 | uint8_t *prev_line = s->previous_frame.data[0] + line*s->previous_frame.linesize[0] + |
| 166 | (width - 1)*s->pixel_size; |
| 167 | |
| 168 | s->length_table[width] = 0; |
| 169 | skipcount = 0; |
| 170 | |
| 171 | /* Initial values */ |
| 172 | lowest_bulk_cost = INT_MAX / 2; |
| 173 | lowest_bulk_cost_index = width; |
| 174 | sec_lowest_bulk_cost = INT_MAX / 2; |
| 175 | sec_lowest_bulk_cost_index = width; |
| 176 | |
| 177 | base_bulk_cost = 1 + s->pixel_size; |
| 178 | |
| 179 | for (i = width - 1; i >= 0; i--) { |
| 180 | |
| 181 | int prev_bulk_cost; |
| 182 | |
| 183 | /* If our lowest bulk cost index is too far away, replace it |
| 184 | * with the next lowest bulk cost */ |
| 185 | if (FFMIN(width, i + MAX_RLE_BULK) < lowest_bulk_cost_index) { |
| 186 | lowest_bulk_cost = sec_lowest_bulk_cost; |
| 187 | lowest_bulk_cost_index = sec_lowest_bulk_cost_index; |
| 188 | |
| 189 | sec_lowest_bulk_cost = INT_MAX / 2; |
| 190 | sec_lowest_bulk_cost_index = width; |
| 191 | } |
| 192 | |
| 193 | /* Deal with the first pixel's bulk cost */ |
| 194 | if (!i) { |
| 195 | base_bulk_cost++; |
| 196 | lowest_bulk_cost++; |
| 197 | sec_lowest_bulk_cost++; |
| 198 | } |
| 199 | |
| 200 | /* Look at the bulk cost of the previous loop and see if it is |
| 201 | * a new lower bulk cost */ |
| 202 | prev_bulk_cost = s->length_table[i + 1] + base_bulk_cost; |
| 203 | if (prev_bulk_cost <= sec_lowest_bulk_cost) { |
| 204 | /* If it's lower than the 2nd lowest, then it may be lower |
| 205 | * than the lowest */ |
| 206 | if (prev_bulk_cost <= lowest_bulk_cost) { |
| 207 | |
| 208 | /* If we have found a new lowest bulk cost, |
| 209 | * then the 2nd lowest bulk cost is now farther than the |
| 210 | * lowest bulk cost, and will never be used */ |
| 211 | sec_lowest_bulk_cost = INT_MAX / 2; |
| 212 | |
| 213 | lowest_bulk_cost = prev_bulk_cost; |
| 214 | lowest_bulk_cost_index = i + 1; |
| 215 | } else { |
| 216 | /* Then it must be the 2nd lowest bulk cost */ |
| 217 | sec_lowest_bulk_cost = prev_bulk_cost; |
| 218 | sec_lowest_bulk_cost_index = i + 1; |
| 219 | } |
| 220 | } |
| 221 | |
| 222 | if (!s->avctx->coded_frame->key_frame && !memcmp(this_line, prev_line, s->pixel_size)) |
| 223 | skipcount = FFMIN(skipcount + 1, MAX_RLE_SKIP); |
| 224 | else |
| 225 | skipcount = 0; |
| 226 | |
| 227 | total_skip_cost = s->length_table[i + skipcount] + 2; |
| 228 | s->skip_table[i] = skipcount; |
| 229 | |
| 230 | |
| 231 | if (i < width - 1 && !memcmp(this_line, this_line + s->pixel_size, s->pixel_size)) |
| 232 | repeatcount = FFMIN(repeatcount + 1, MAX_RLE_REPEAT); |
| 233 | else |
| 234 | repeatcount = 1; |
| 235 | |
| 236 | total_repeat_cost = s->length_table[i + repeatcount] + 1 + s->pixel_size; |
| 237 | |
| 238 | /* skip code is free for the first pixel, it costs one byte for repeat and bulk copy |
| 239 | * so let's make it aware */ |
| 240 | if (i == 0) { |
| 241 | total_skip_cost--; |
| 242 | total_repeat_cost++; |
| 243 | } |
| 244 | |
| 245 | if (repeatcount > 1 && (skipcount == 0 || total_repeat_cost < total_skip_cost)) { |
| 246 | /* repeat is the best */ |
| 247 | s->length_table[i] = total_repeat_cost; |
| 248 | s->rlecode_table[i] = -repeatcount; |
| 249 | } |
| 250 | else if (skipcount > 0) { |
| 251 | /* skip is the best choice here */ |
| 252 | s->length_table[i] = total_skip_cost; |
| 253 | s->rlecode_table[i] = 0; |
| 254 | } |
| 255 | else { |
| 256 | /* We cannot do neither skip nor repeat |
| 257 | * thus we use the best bulk copy */ |
| 258 | |
| 259 | s->length_table[i] = lowest_bulk_cost; |
| 260 | s->rlecode_table[i] = lowest_bulk_cost_index - i; |
| 261 | |
| 262 | } |
| 263 | |
| 264 | /* These bulk costs increase every iteration */ |
| 265 | lowest_bulk_cost += s->pixel_size; |
| 266 | sec_lowest_bulk_cost += s->pixel_size; |
| 267 | |
| 268 | this_line -= s->pixel_size; |
| 269 | prev_line -= s->pixel_size; |
| 270 | } |
| 271 | |
| 272 | /* Good ! Now we have the best sequence for this line, let's output it */ |
| 273 | |
| 274 | /* We do a special case for the first pixel so that we avoid testing it in |
| 275 | * the whole loop */ |
| 276 | |
| 277 | i=0; |
| 278 | this_line = p-> data[0] + line*p->linesize[0]; |
| 279 | |
| 280 | if (s->rlecode_table[0] == 0) { |
| 281 | bytestream_put_byte(buf, s->skip_table[0] + 1); |
| 282 | i += s->skip_table[0]; |
| 283 | } |
| 284 | else bytestream_put_byte(buf, 1); |
| 285 | |
| 286 | |
| 287 | while (i < width) { |
| 288 | rlecode = s->rlecode_table[i]; |
| 289 | bytestream_put_byte(buf, rlecode); |
| 290 | if (rlecode == 0) { |
| 291 | /* Write a skip sequence */ |
| 292 | bytestream_put_byte(buf, s->skip_table[i] + 1); |
| 293 | i += s->skip_table[i]; |
| 294 | } |
| 295 | else if (rlecode > 0) { |
| 296 | /* bulk copy */ |
| 297 | if (s->avctx->pix_fmt == AV_PIX_FMT_GRAY8) { |
| 298 | int j; |
| 299 | // QT grayscale colorspace has 0=white and 255=black, we will |
| 300 | // ignore the palette that is included in the AVFrame because |
| 301 | // AV_PIX_FMT_GRAY8 has defined color mapping |
| 302 | for (j = 0; j < rlecode*s->pixel_size; ++j) |
| 303 | bytestream_put_byte(buf, *(this_line + i*s->pixel_size + j) ^ 0xff); |
| 304 | } else { |
| 305 | bytestream_put_buffer(buf, this_line + i*s->pixel_size, rlecode*s->pixel_size); |
| 306 | } |
| 307 | i += rlecode; |
| 308 | } |
| 309 | else { |
| 310 | /* repeat the bits */ |
| 311 | if (s->avctx->pix_fmt == AV_PIX_FMT_GRAY8) { |
| 312 | int j; |
| 313 | // QT grayscale colorspace has 0=white and 255=black, ... |
| 314 | for (j = 0; j < s->pixel_size; ++j) |
| 315 | bytestream_put_byte(buf, *(this_line + i*s->pixel_size + j) ^ 0xff); |
| 316 | } else { |
| 317 | bytestream_put_buffer(buf, this_line + i*s->pixel_size, s->pixel_size); |
| 318 | } |
| 319 | i -= rlecode; |
| 320 | } |
| 321 | } |
| 322 | bytestream_put_byte(buf, -1); // end RLE line |
| 323 | } |
| 324 | |
| 325 | /** Encode frame including header */ |
| 326 | static int encode_frame(QtrleEncContext *s, const AVFrame *p, uint8_t *buf) |
| 327 | { |
| 328 | int i; |
| 329 | int start_line = 0; |
| 330 | int end_line = s->avctx->height; |
| 331 | uint8_t *orig_buf = buf; |
| 332 | |
| 333 | if (!s->avctx->coded_frame->key_frame) { |
| 334 | unsigned line_size = s->logical_width * s->pixel_size; |
| 335 | for (start_line = 0; start_line < s->avctx->height; start_line++) |
| 336 | if (memcmp(p->data[0] + start_line*p->linesize[0], |
| 337 | s->previous_frame.data[0] + start_line*s->previous_frame.linesize[0], |
| 338 | line_size)) |
| 339 | break; |
| 340 | |
| 341 | for (end_line=s->avctx->height; end_line > start_line; end_line--) |
| 342 | if (memcmp(p->data[0] + (end_line - 1)*p->linesize[0], |
| 343 | s->previous_frame.data[0] + (end_line - 1)*s->previous_frame.linesize[0], |
| 344 | line_size)) |
| 345 | break; |
| 346 | } |
| 347 | |
| 348 | bytestream_put_be32(&buf, 0); // CHUNK SIZE, patched later |
| 349 | |
| 350 | if ((start_line == 0 && end_line == s->avctx->height) || start_line == s->avctx->height) |
| 351 | bytestream_put_be16(&buf, 0); // header |
| 352 | else { |
| 353 | bytestream_put_be16(&buf, 8); // header |
| 354 | bytestream_put_be16(&buf, start_line); // starting line |
| 355 | bytestream_put_be16(&buf, 0); // unknown |
| 356 | bytestream_put_be16(&buf, end_line - start_line); // lines to update |
| 357 | bytestream_put_be16(&buf, 0); // unknown |
| 358 | } |
| 359 | for (i = start_line; i < end_line; i++) |
| 360 | qtrle_encode_line(s, p, i, &buf); |
| 361 | |
| 362 | bytestream_put_byte(&buf, 0); // zero skip code = frame finished |
| 363 | AV_WB32(orig_buf, buf - orig_buf); // patch the chunk size |
| 364 | return buf - orig_buf; |
| 365 | } |
| 366 | |
| 367 | static int qtrle_encode_frame(AVCodecContext *avctx, AVPacket *pkt, |
| 368 | const AVFrame *pict, int *got_packet) |
| 369 | { |
| 370 | QtrleEncContext * const s = avctx->priv_data; |
| 371 | AVFrame * const p = avctx->coded_frame; |
| 372 | int ret; |
| 373 | |
| 374 | if ((ret = ff_alloc_packet2(avctx, pkt, s->max_buf_size)) < 0) |
| 375 | return ret; |
| 376 | |
| 377 | if (avctx->gop_size == 0 || (s->avctx->frame_number % avctx->gop_size) == 0) { |
| 378 | /* I-Frame */ |
| 379 | p->pict_type = AV_PICTURE_TYPE_I; |
| 380 | p->key_frame = 1; |
| 381 | } else { |
| 382 | /* P-Frame */ |
| 383 | p->pict_type = AV_PICTURE_TYPE_P; |
| 384 | p->key_frame = 0; |
| 385 | } |
| 386 | |
| 387 | pkt->size = encode_frame(s, pict, pkt->data); |
| 388 | |
| 389 | /* save the current frame */ |
| 390 | av_picture_copy(&s->previous_frame, (const AVPicture *)pict, |
| 391 | avctx->pix_fmt, avctx->width, avctx->height); |
| 392 | |
| 393 | if (p->key_frame) |
| 394 | pkt->flags |= AV_PKT_FLAG_KEY; |
| 395 | *got_packet = 1; |
| 396 | |
| 397 | return 0; |
| 398 | } |
| 399 | |
| 400 | AVCodec ff_qtrle_encoder = { |
| 401 | .name = "qtrle", |
| 402 | .long_name = NULL_IF_CONFIG_SMALL("QuickTime Animation (RLE) video"), |
| 403 | .type = AVMEDIA_TYPE_VIDEO, |
| 404 | .id = AV_CODEC_ID_QTRLE, |
| 405 | .priv_data_size = sizeof(QtrleEncContext), |
| 406 | .init = qtrle_encode_init, |
| 407 | .encode2 = qtrle_encode_frame, |
| 408 | .close = qtrle_encode_end, |
| 409 | .pix_fmts = (const enum AVPixelFormat[]){ |
| 410 | AV_PIX_FMT_RGB24, AV_PIX_FMT_RGB555BE, AV_PIX_FMT_ARGB, AV_PIX_FMT_GRAY8, AV_PIX_FMT_NONE |
| 411 | }, |
| 412 | }; |