00001 /* 00002 * Quicktime Animation (RLE) Video Encoder 00003 * Copyright (C) 2007 Clemens Fruhwirth 00004 * Copyright (C) 2007 Alexis Ballier 00005 * 00006 * This file is based on flashsvenc.c. 00007 * 00008 * This file is part of FFmpeg. 00009 * 00010 * FFmpeg is free software; you can redistribute it and/or 00011 * modify it under the terms of the GNU Lesser General Public 00012 * License as published by the Free Software Foundation; either 00013 * version 2.1 of the License, or (at your option) any later version. 00014 * 00015 * FFmpeg is distributed in the hope that it will be useful, 00016 * but WITHOUT ANY WARRANTY; without even the implied warranty of 00017 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 00018 * Lesser General Public License for more details. 00019 * 00020 * You should have received a copy of the GNU Lesser General Public 00021 * License along with FFmpeg; if not, write to the Free Software 00022 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 00023 */ 00024 00025 #include "avcodec.h" 00026 #include "bytestream.h" 00027 00029 #define MAX_RLE_BULK 127 00030 00031 #define MAX_RLE_REPEAT 128 00032 00033 #define MAX_RLE_SKIP 254 00034 00035 typedef struct QtrleEncContext { 00036 AVCodecContext *avctx; 00037 AVFrame frame; 00038 int pixel_size; 00039 AVPicture previous_frame; 00040 unsigned int max_buf_size; 00050 signed char *rlecode_table; 00054 int *length_table; 00058 uint8_t* skip_table; 00059 } QtrleEncContext; 00060 00061 static av_cold int qtrle_encode_init(AVCodecContext *avctx) 00062 { 00063 QtrleEncContext *s = avctx->priv_data; 00064 00065 if (avcodec_check_dimensions(avctx, avctx->width, avctx->height) < 0) { 00066 return -1; 00067 } 00068 s->avctx=avctx; 00069 00070 switch (avctx->pix_fmt) { 00071 /* case PIX_FMT_RGB555: 00072 s->pixel_size = 2; 00073 break;*/ 00074 case PIX_FMT_RGB24: 00075 s->pixel_size = 3; 00076 break; 00077 default: 00078 av_log(avctx, AV_LOG_ERROR, "Unsupported colorspace.\n"); 00079 break; 00080 } 00081 avctx->bits_per_coded_sample = s->pixel_size*8; 00082 00083 s->rlecode_table = av_mallocz(s->avctx->width); 00084 s->skip_table = av_mallocz(s->avctx->width); 00085 s->length_table = av_mallocz((s->avctx->width + 1)*sizeof(int)); 00086 if (!s->skip_table || !s->length_table || !s->rlecode_table) { 00087 av_log(avctx, AV_LOG_ERROR, "Error allocating memory.\n"); 00088 return -1; 00089 } 00090 if (avpicture_alloc(&s->previous_frame, avctx->pix_fmt, avctx->width, avctx->height) < 0) { 00091 av_log(avctx, AV_LOG_ERROR, "Error allocating picture\n"); 00092 return -1; 00093 } 00094 00095 s->max_buf_size = s->avctx->width*s->avctx->height*s->pixel_size /* image base material */ 00096 + 15 /* header + footer */ 00097 + s->avctx->height*2 /* skip code+rle end */ 00098 + s->avctx->width/MAX_RLE_BULK + 1 /* rle codes */; 00099 avctx->coded_frame = &s->frame; 00100 return 0; 00101 } 00102 00106 static void qtrle_encode_line(QtrleEncContext *s, AVFrame *p, int line, uint8_t **buf) 00107 { 00108 int width=s->avctx->width; 00109 int i; 00110 signed char rlecode; 00111 00112 /* We will use it to compute the best bulk copy sequence */ 00113 unsigned int bulkcount; 00114 /* This will be the number of pixels equal to the preivous frame one's 00115 * starting from the ith pixel */ 00116 unsigned int skipcount; 00117 /* This will be the number of consecutive equal pixels in the current 00118 * frame, starting from the ith one also */ 00119 unsigned int av_uninit(repeatcount); 00120 00121 /* The cost of the three different possibilities */ 00122 int total_bulk_cost; 00123 int total_skip_cost; 00124 int total_repeat_cost; 00125 00126 int temp_cost; 00127 int j; 00128 00129 uint8_t *this_line = p-> data[0] + line*p->linesize[0] + (width - 1)*s->pixel_size; 00130 uint8_t *prev_line = s->previous_frame.data[0] + line*p->linesize[0] + (width - 1)*s->pixel_size; 00131 00132 s->length_table[width] = 0; 00133 skipcount = 0; 00134 00135 for (i = width - 1; i >= 0; i--) { 00136 00137 if (!s->frame.key_frame && !memcmp(this_line, prev_line, s->pixel_size)) 00138 skipcount = FFMIN(skipcount + 1, MAX_RLE_SKIP); 00139 else 00140 skipcount = 0; 00141 00142 total_skip_cost = s->length_table[i + skipcount] + 2; 00143 s->skip_table[i] = skipcount; 00144 00145 00146 if (i < width - 1 && !memcmp(this_line, this_line + s->pixel_size, s->pixel_size)) 00147 repeatcount = FFMIN(repeatcount + 1, MAX_RLE_REPEAT); 00148 else 00149 repeatcount = 1; 00150 00151 total_repeat_cost = s->length_table[i + repeatcount] + 1 + s->pixel_size; 00152 00153 /* skip code is free for the first pixel, it costs one byte for repeat and bulk copy 00154 * so let's make it aware */ 00155 if (i == 0) { 00156 total_skip_cost--; 00157 total_repeat_cost++; 00158 } 00159 00160 if (repeatcount > 1 && (skipcount == 0 || total_repeat_cost < total_skip_cost)) { 00161 /* repeat is the best */ 00162 s->length_table[i] = total_repeat_cost; 00163 s->rlecode_table[i] = -repeatcount; 00164 } 00165 else if (skipcount > 0) { 00166 /* skip is the best choice here */ 00167 s->length_table[i] = total_skip_cost; 00168 s->rlecode_table[i] = 0; 00169 } 00170 else { 00171 /* We cannot do neither skip nor repeat 00172 * thus we search for the best bulk copy to do */ 00173 00174 int limit = FFMIN(width - i, MAX_RLE_BULK); 00175 00176 temp_cost = 1 + s->pixel_size + !i; 00177 total_bulk_cost = INT_MAX; 00178 00179 for (j = 1; j <= limit; j++) { 00180 if (s->length_table[i + j] + temp_cost < total_bulk_cost) { 00181 /* We have found a better bulk copy ... */ 00182 total_bulk_cost = s->length_table[i + j] + temp_cost; 00183 bulkcount = j; 00184 } 00185 temp_cost += s->pixel_size; 00186 } 00187 00188 s->length_table[i] = total_bulk_cost; 00189 s->rlecode_table[i] = bulkcount; 00190 } 00191 00192 this_line -= s->pixel_size; 00193 prev_line -= s->pixel_size; 00194 } 00195 00196 /* Good ! Now we have the best sequence for this line, let's ouput it */ 00197 00198 /* We do a special case for the first pixel so that we avoid testing it in 00199 * the whole loop */ 00200 00201 i=0; 00202 this_line = p-> data[0] + line*p->linesize[0]; 00203 prev_line = s->previous_frame.data[0] + line*p->linesize[0]; 00204 00205 if (s->rlecode_table[0] == 0) { 00206 bytestream_put_byte(buf, s->skip_table[0] + 1); 00207 i += s->skip_table[0]; 00208 } 00209 else bytestream_put_byte(buf, 1); 00210 00211 00212 while (i < width) { 00213 rlecode = s->rlecode_table[i]; 00214 bytestream_put_byte(buf, rlecode); 00215 if (rlecode == 0) { 00216 /* Write a skip sequence */ 00217 bytestream_put_byte(buf, s->skip_table[i] + 1); 00218 i += s->skip_table[i]; 00219 } 00220 else if (rlecode > 0) { 00221 /* bulk copy */ 00222 bytestream_put_buffer(buf, this_line + i*s->pixel_size, rlecode*s->pixel_size); 00223 i += rlecode; 00224 } 00225 else { 00226 /* repeat the bits */ 00227 bytestream_put_buffer(buf, this_line + i*s->pixel_size, s->pixel_size); 00228 i -= rlecode; 00229 } 00230 } 00231 bytestream_put_byte(buf, -1); // end RLE line 00232 } 00233 00235 static int encode_frame(QtrleEncContext *s, AVFrame *p, uint8_t *buf) 00236 { 00237 int i; 00238 int start_line = 0; 00239 int end_line = s->avctx->height; 00240 uint8_t *orig_buf = buf; 00241 00242 if (!s->frame.key_frame) { 00243 for (start_line = 0; start_line < s->avctx->height; start_line++) 00244 if (memcmp(p->data[0] + start_line*p->linesize[0], 00245 s->previous_frame.data[0] + start_line*p->linesize[0], 00246 p->linesize[0])) 00247 break; 00248 00249 for (end_line=s->avctx->height; end_line > start_line; end_line--) 00250 if (memcmp(p->data[0] + (end_line - 1)*p->linesize[0], 00251 s->previous_frame.data[0] + (end_line - 1)*p->linesize[0], 00252 p->linesize[0])) 00253 break; 00254 } 00255 00256 bytestream_put_be32(&buf, 0); // CHUNK SIZE, patched later 00257 00258 if ((start_line == 0 && end_line == s->avctx->height) || start_line == s->avctx->height) 00259 bytestream_put_be16(&buf, 0); // header 00260 else { 00261 bytestream_put_be16(&buf, 8); // header 00262 bytestream_put_be16(&buf, start_line); // starting line 00263 bytestream_put_be16(&buf, 0); // unknown 00264 bytestream_put_be16(&buf, end_line - start_line); // lines to update 00265 bytestream_put_be16(&buf, 0); // unknown 00266 } 00267 for (i = start_line; i < end_line; i++) 00268 qtrle_encode_line(s, p, i, &buf); 00269 00270 bytestream_put_byte(&buf, 0); // zero skip code = frame finished 00271 AV_WB32(orig_buf, buf - orig_buf); // patch the chunk size 00272 return buf - orig_buf; 00273 } 00274 00275 static int qtrle_encode_frame(AVCodecContext *avctx, uint8_t *buf, int buf_size, void *data) 00276 { 00277 QtrleEncContext * const s = avctx->priv_data; 00278 AVFrame *pict = data; 00279 AVFrame * const p = &s->frame; 00280 int chunksize; 00281 00282 *p = *pict; 00283 00284 if (buf_size < s->max_buf_size) { 00285 /* Upper bound check for compressed data */ 00286 av_log(avctx, AV_LOG_ERROR, "buf_size %d < %d\n", buf_size, s->max_buf_size); 00287 return -1; 00288 } 00289 00290 if (avctx->gop_size == 0 || (s->avctx->frame_number % avctx->gop_size) == 0) { 00291 /* I-Frame */ 00292 p->pict_type = FF_I_TYPE; 00293 p->key_frame = 1; 00294 } else { 00295 /* P-Frame */ 00296 p->pict_type = FF_P_TYPE; 00297 p->key_frame = 0; 00298 } 00299 00300 chunksize = encode_frame(s, pict, buf); 00301 00302 /* save the current frame */ 00303 av_picture_copy(&s->previous_frame, (AVPicture *)p, avctx->pix_fmt, avctx->width, avctx->height); 00304 return chunksize; 00305 } 00306 00307 static av_cold int qtrle_encode_end(AVCodecContext *avctx) 00308 { 00309 QtrleEncContext *s = avctx->priv_data; 00310 00311 avpicture_free(&s->previous_frame); 00312 av_free(s->rlecode_table); 00313 av_free(s->length_table); 00314 av_free(s->skip_table); 00315 return 0; 00316 } 00317 00318 AVCodec qtrle_encoder = { 00319 "qtrle", 00320 CODEC_TYPE_VIDEO, 00321 CODEC_ID_QTRLE, 00322 sizeof(QtrleEncContext), 00323 qtrle_encode_init, 00324 qtrle_encode_frame, 00325 qtrle_encode_end, 00326 .pix_fmts = (enum PixelFormat[]){PIX_FMT_RGB24, PIX_FMT_NONE}, 00327 .long_name = NULL_IF_CONFIG_SMALL("QuickTime Animation (RLE) video"), 00328 };