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 "avcodec.h" 26#include "bytestream.h" 27 28/** Maximum RLE code for bulk copy */ 29#define MAX_RLE_BULK 127 30/** Maximum RLE code for repeat */ 31#define MAX_RLE_REPEAT 128 32/** Maximum RLE code for skip */ 33#define MAX_RLE_SKIP 254 34 35typedef struct QtrleEncContext { 36 AVCodecContext *avctx; 37 AVFrame frame; 38 int pixel_size; 39 AVPicture previous_frame; 40 unsigned int max_buf_size; 41 /** 42 * This array will contain at ith position the value of the best RLE code 43 * if the line started at pixel i 44 * There can be 3 values : 45 * skip (0) : skip as much as possible pixels because they are equal to the 46 * previous frame ones 47 * repeat (<-1) : repeat that pixel -rle_code times, still as much as 48 * possible 49 * copy (>0) : copy the raw next rle_code pixels */ 50 signed char *rlecode_table; 51 /** 52 * This array will contain the length of the best rle encoding of the line 53 * starting at ith pixel */ 54 int *length_table; 55 /** 56 * Will contain at ith position the number of consecutive pixels equal to the previous 57 * frame starting from pixel i */ 58 uint8_t* skip_table; 59} QtrleEncContext; 60 61static av_cold int qtrle_encode_init(AVCodecContext *avctx) 62{ 63 QtrleEncContext *s = avctx->priv_data; 64 65 if (avcodec_check_dimensions(avctx, avctx->width, avctx->height) < 0) { 66 return -1; 67 } 68 s->avctx=avctx; 69 70 switch (avctx->pix_fmt) { 71 case PIX_FMT_RGB555BE: 72 s->pixel_size = 2; 73 break; 74 case PIX_FMT_RGB24: 75 s->pixel_size = 3; 76 break; 77 case PIX_FMT_ARGB: 78 s->pixel_size = 4; 79 break; 80 default: 81 av_log(avctx, AV_LOG_ERROR, "Unsupported colorspace.\n"); 82 break; 83 } 84 avctx->bits_per_coded_sample = s->pixel_size*8; 85 86 s->rlecode_table = av_mallocz(s->avctx->width); 87 s->skip_table = av_mallocz(s->avctx->width); 88 s->length_table = av_mallocz((s->avctx->width + 1)*sizeof(int)); 89 if (!s->skip_table || !s->length_table || !s->rlecode_table) { 90 av_log(avctx, AV_LOG_ERROR, "Error allocating memory.\n"); 91 return -1; 92 } 93 if (avpicture_alloc(&s->previous_frame, avctx->pix_fmt, avctx->width, avctx->height) < 0) { 94 av_log(avctx, AV_LOG_ERROR, "Error allocating picture\n"); 95 return -1; 96 } 97 98 s->max_buf_size = s->avctx->width*s->avctx->height*s->pixel_size /* image base material */ 99 + 15 /* header + footer */ 100 + s->avctx->height*2 /* skip code+rle end */ 101 + s->avctx->width/MAX_RLE_BULK + 1 /* rle codes */; 102 avctx->coded_frame = &s->frame; 103 return 0; 104} 105 106/** 107 * Computes the best RLE sequence for a line 108 */ 109static void qtrle_encode_line(QtrleEncContext *s, AVFrame *p, int line, uint8_t **buf) 110{ 111 int width=s->avctx->width; 112 int i; 113 signed char rlecode; 114 115 /* We will use it to compute the best bulk copy sequence */ 116 unsigned int bulkcount; 117 /* This will be the number of pixels equal to the preivous frame one's 118 * starting from the ith pixel */ 119 unsigned int skipcount; 120 /* This will be the number of consecutive equal pixels in the current 121 * frame, starting from the ith one also */ 122 unsigned int av_uninit(repeatcount); 123 124 /* The cost of the three different possibilities */ 125 int total_bulk_cost; 126 int total_skip_cost; 127 int total_repeat_cost; 128 129 int temp_cost; 130 int j; 131 132 uint8_t *this_line = p-> data[0] + line*p-> linesize[0] + 133 (width - 1)*s->pixel_size; 134 uint8_t *prev_line = s->previous_frame.data[0] + line*s->previous_frame.linesize[0] + 135 (width - 1)*s->pixel_size; 136 137 s->length_table[width] = 0; 138 skipcount = 0; 139 140 for (i = width - 1; i >= 0; i--) { 141 142 if (!s->frame.key_frame && !memcmp(this_line, prev_line, s->pixel_size)) 143 skipcount = FFMIN(skipcount + 1, MAX_RLE_SKIP); 144 else 145 skipcount = 0; 146 147 total_skip_cost = s->length_table[i + skipcount] + 2; 148 s->skip_table[i] = skipcount; 149 150 151 if (i < width - 1 && !memcmp(this_line, this_line + s->pixel_size, s->pixel_size)) 152 repeatcount = FFMIN(repeatcount + 1, MAX_RLE_REPEAT); 153 else 154 repeatcount = 1; 155 156 total_repeat_cost = s->length_table[i + repeatcount] + 1 + s->pixel_size; 157 158 /* skip code is free for the first pixel, it costs one byte for repeat and bulk copy 159 * so let's make it aware */ 160 if (i == 0) { 161 total_skip_cost--; 162 total_repeat_cost++; 163 } 164 165 if (repeatcount > 1 && (skipcount == 0 || total_repeat_cost < total_skip_cost)) { 166 /* repeat is the best */ 167 s->length_table[i] = total_repeat_cost; 168 s->rlecode_table[i] = -repeatcount; 169 } 170 else if (skipcount > 0) { 171 /* skip is the best choice here */ 172 s->length_table[i] = total_skip_cost; 173 s->rlecode_table[i] = 0; 174 } 175 else { 176 /* We cannot do neither skip nor repeat 177 * thus we search for the best bulk copy to do */ 178 179 int limit = FFMIN(width - i, MAX_RLE_BULK); 180 181 temp_cost = 1 + s->pixel_size + !i; 182 total_bulk_cost = INT_MAX; 183 184 for (j = 1; j <= limit; j++) { 185 if (s->length_table[i + j] + temp_cost < total_bulk_cost) { 186 /* We have found a better bulk copy ... */ 187 total_bulk_cost = s->length_table[i + j] + temp_cost; 188 bulkcount = j; 189 } 190 temp_cost += s->pixel_size; 191 } 192 193 s->length_table[i] = total_bulk_cost; 194 s->rlecode_table[i] = bulkcount; 195 } 196 197 this_line -= s->pixel_size; 198 prev_line -= s->pixel_size; 199 } 200 201 /* Good ! Now we have the best sequence for this line, let's ouput it */ 202 203 /* We do a special case for the first pixel so that we avoid testing it in 204 * the whole loop */ 205 206 i=0; 207 this_line = p-> data[0] + line*p->linesize[0]; 208 209 if (s->rlecode_table[0] == 0) { 210 bytestream_put_byte(buf, s->skip_table[0] + 1); 211 i += s->skip_table[0]; 212 } 213 else bytestream_put_byte(buf, 1); 214 215 216 while (i < width) { 217 rlecode = s->rlecode_table[i]; 218 bytestream_put_byte(buf, rlecode); 219 if (rlecode == 0) { 220 /* Write a skip sequence */ 221 bytestream_put_byte(buf, s->skip_table[i] + 1); 222 i += s->skip_table[i]; 223 } 224 else if (rlecode > 0) { 225 /* bulk copy */ 226 bytestream_put_buffer(buf, this_line + i*s->pixel_size, rlecode*s->pixel_size); 227 i += rlecode; 228 } 229 else { 230 /* repeat the bits */ 231 bytestream_put_buffer(buf, this_line + i*s->pixel_size, s->pixel_size); 232 i -= rlecode; 233 } 234 } 235 bytestream_put_byte(buf, -1); // end RLE line 236} 237 238/** Encodes frame including header */ 239static int encode_frame(QtrleEncContext *s, AVFrame *p, uint8_t *buf) 240{ 241 int i; 242 int start_line = 0; 243 int end_line = s->avctx->height; 244 uint8_t *orig_buf = buf; 245 246 if (!s->frame.key_frame) { 247 unsigned line_size = s->avctx->width * s->pixel_size; 248 for (start_line = 0; start_line < s->avctx->height; start_line++) 249 if (memcmp(p->data[0] + start_line*p->linesize[0], 250 s->previous_frame.data[0] + start_line*s->previous_frame.linesize[0], 251 line_size)) 252 break; 253 254 for (end_line=s->avctx->height; end_line > start_line; end_line--) 255 if (memcmp(p->data[0] + (end_line - 1)*p->linesize[0], 256 s->previous_frame.data[0] + (end_line - 1)*s->previous_frame.linesize[0], 257 line_size)) 258 break; 259 } 260 261 bytestream_put_be32(&buf, 0); // CHUNK SIZE, patched later 262 263 if ((start_line == 0 && end_line == s->avctx->height) || start_line == s->avctx->height) 264 bytestream_put_be16(&buf, 0); // header 265 else { 266 bytestream_put_be16(&buf, 8); // header 267 bytestream_put_be16(&buf, start_line); // starting line 268 bytestream_put_be16(&buf, 0); // unknown 269 bytestream_put_be16(&buf, end_line - start_line); // lines to update 270 bytestream_put_be16(&buf, 0); // unknown 271 } 272 for (i = start_line; i < end_line; i++) 273 qtrle_encode_line(s, p, i, &buf); 274 275 bytestream_put_byte(&buf, 0); // zero skip code = frame finished 276 AV_WB32(orig_buf, buf - orig_buf); // patch the chunk size 277 return buf - orig_buf; 278} 279 280static int qtrle_encode_frame(AVCodecContext *avctx, uint8_t *buf, int buf_size, void *data) 281{ 282 QtrleEncContext * const s = avctx->priv_data; 283 AVFrame *pict = data; 284 AVFrame * const p = &s->frame; 285 int chunksize; 286 287 *p = *pict; 288 289 if (buf_size < s->max_buf_size) { 290 /* Upper bound check for compressed data */ 291 av_log(avctx, AV_LOG_ERROR, "buf_size %d < %d\n", buf_size, s->max_buf_size); 292 return -1; 293 } 294 295 if (avctx->gop_size == 0 || (s->avctx->frame_number % avctx->gop_size) == 0) { 296 /* I-Frame */ 297 p->pict_type = FF_I_TYPE; 298 p->key_frame = 1; 299 } else { 300 /* P-Frame */ 301 p->pict_type = FF_P_TYPE; 302 p->key_frame = 0; 303 } 304 305 chunksize = encode_frame(s, pict, buf); 306 307 /* save the current frame */ 308 av_picture_copy(&s->previous_frame, (AVPicture *)p, avctx->pix_fmt, avctx->width, avctx->height); 309 return chunksize; 310} 311 312static av_cold int qtrle_encode_end(AVCodecContext *avctx) 313{ 314 QtrleEncContext *s = avctx->priv_data; 315 316 avpicture_free(&s->previous_frame); 317 av_free(s->rlecode_table); 318 av_free(s->length_table); 319 av_free(s->skip_table); 320 return 0; 321} 322 323AVCodec qtrle_encoder = { 324 "qtrle", 325 AVMEDIA_TYPE_VIDEO, 326 CODEC_ID_QTRLE, 327 sizeof(QtrleEncContext), 328 qtrle_encode_init, 329 qtrle_encode_frame, 330 qtrle_encode_end, 331 .pix_fmts = (const enum PixelFormat[]){PIX_FMT_RGB24, PIX_FMT_RGB555BE, PIX_FMT_ARGB, PIX_FMT_NONE}, 332 .long_name = NULL_IF_CONFIG_SMALL("QuickTime Animation (RLE) video"), 333}; 334