2 * BMP image format decoder
3 * Copyright (c) 2005 Mans Rullgard
5 * This file is part of Libav.
7 * Libav 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.
12 * Libav 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.
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with Libav; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
23 #include "bytestream.h"
27 static av_cold int bmp_decode_init(AVCodecContext *avctx){
28 BMPContext *s = avctx->priv_data;
30 avcodec_get_frame_defaults((AVFrame*)&s->picture);
31 avctx->coded_frame = (AVFrame*)&s->picture;
36 static int bmp_decode_frame(AVCodecContext *avctx,
37 void *data, int *data_size,
40 const uint8_t *buf = avpkt->data;
41 int buf_size = avpkt->size;
42 BMPContext *s = avctx->priv_data;
43 AVFrame *picture = data;
44 AVFrame *p = &s->picture;
45 unsigned int fsize, hsize;
50 int i, j, n, linesize;
54 const uint8_t *buf0 = buf;
57 av_log(avctx, AV_LOG_ERROR, "buf size too small (%d)\n", buf_size);
61 if(bytestream_get_byte(&buf) != 'B' ||
62 bytestream_get_byte(&buf) != 'M') {
63 av_log(avctx, AV_LOG_ERROR, "bad magic number\n");
67 fsize = bytestream_get_le32(&buf);
69 av_log(avctx, AV_LOG_ERROR, "not enough data (%d < %d), trying to decode anyway\n",
74 buf += 2; /* reserved1 */
75 buf += 2; /* reserved2 */
77 hsize = bytestream_get_le32(&buf); /* header size */
78 ihsize = bytestream_get_le32(&buf); /* more header size */
79 if(ihsize + 14 > hsize){
80 av_log(avctx, AV_LOG_ERROR, "invalid header size %d\n", hsize);
84 /* sometimes file size is set to some headers size, set a real size in that case */
85 if(fsize == 14 || fsize == ihsize + 14)
89 av_log(avctx, AV_LOG_ERROR, "declared file size is less than header size (%d < %d)\n",
97 case 108: // windib v4
98 case 124: // windib v5
99 width = bytestream_get_le32(&buf);
100 height = bytestream_get_le32(&buf);
103 width = bytestream_get_le16(&buf);
104 height = bytestream_get_le16(&buf);
107 av_log(avctx, AV_LOG_ERROR, "unsupported BMP file, patch welcome\n");
111 if(bytestream_get_le16(&buf) != 1){ /* planes */
112 av_log(avctx, AV_LOG_ERROR, "invalid BMP header\n");
116 depth = bytestream_get_le16(&buf);
119 comp = bytestream_get_le32(&buf);
123 if(comp != BMP_RGB && comp != BMP_BITFIELDS && comp != BMP_RLE4 && comp != BMP_RLE8){
124 av_log(avctx, AV_LOG_ERROR, "BMP coding %d not supported\n", comp);
128 if(comp == BMP_BITFIELDS){
130 rgb[0] = bytestream_get_le32(&buf);
131 rgb[1] = bytestream_get_le32(&buf);
132 rgb[2] = bytestream_get_le32(&buf);
135 avctx->width = width;
136 avctx->height = height > 0? height: -height;
138 avctx->pix_fmt = PIX_FMT_NONE;
142 if(comp == BMP_BITFIELDS){
143 rgb[0] = (rgb[0] >> 15) & 3;
144 rgb[1] = (rgb[1] >> 15) & 3;
145 rgb[2] = (rgb[2] >> 15) & 3;
147 if(rgb[0] + rgb[1] + rgb[2] != 3 ||
148 rgb[0] == rgb[1] || rgb[0] == rgb[2] || rgb[1] == rgb[2]){
157 avctx->pix_fmt = PIX_FMT_BGR24;
160 avctx->pix_fmt = PIX_FMT_BGR24;
164 avctx->pix_fmt = PIX_FMT_RGB555;
165 else if (comp == BMP_BITFIELDS) {
166 if (rgb[0] == 0xF800 && rgb[1] == 0x07E0 && rgb[2] == 0x001F)
167 avctx->pix_fmt = PIX_FMT_RGB565;
168 else if (rgb[0] == 0x7C00 && rgb[1] == 0x03E0 && rgb[2] == 0x001F)
169 avctx->pix_fmt = PIX_FMT_RGB555;
170 else if (rgb[0] == 0x0F00 && rgb[1] == 0x00F0 && rgb[2] == 0x000F)
171 avctx->pix_fmt = PIX_FMT_RGB444;
173 av_log(avctx, AV_LOG_ERROR, "Unknown bitfields %0X %0X %0X\n", rgb[0], rgb[1], rgb[2]);
174 return AVERROR(EINVAL);
179 if(hsize - ihsize - 14 > 0)
180 avctx->pix_fmt = PIX_FMT_PAL8;
182 avctx->pix_fmt = PIX_FMT_GRAY8;
186 if(hsize - ihsize - 14 > 0){
187 avctx->pix_fmt = PIX_FMT_PAL8;
189 av_log(avctx, AV_LOG_ERROR, "Unknown palette for %d-colour BMP\n", 1<<depth);
194 av_log(avctx, AV_LOG_ERROR, "depth %d not supported\n", depth);
198 if(avctx->pix_fmt == PIX_FMT_NONE){
199 av_log(avctx, AV_LOG_ERROR, "unsupported pixel format\n");
204 avctx->release_buffer(avctx, p);
207 if(avctx->get_buffer(avctx, p) < 0){
208 av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
211 p->pict_type = AV_PICTURE_TYPE_I;
215 dsize = buf_size - hsize;
217 /* Line size in file multiple of 4 */
218 n = ((avctx->width * depth) / 8 + 3) & ~3;
220 if(n * avctx->height > dsize && comp != BMP_RLE4 && comp != BMP_RLE8){
221 av_log(avctx, AV_LOG_ERROR, "not enough data (%d < %d)\n",
222 dsize, n * avctx->height);
226 // RLE may skip decoding some picture areas, so blank picture before decoding
227 if(comp == BMP_RLE4 || comp == BMP_RLE8)
228 memset(p->data[0], 0, avctx->height * p->linesize[0]);
230 if(depth == 4 || depth == 8)
231 memset(p->data[1], 0, 1024);
234 ptr = p->data[0] + (avctx->height - 1) * p->linesize[0];
235 linesize = -p->linesize[0];
238 linesize = p->linesize[0];
241 if(avctx->pix_fmt == PIX_FMT_PAL8){
242 int colors = 1 << depth;
246 t = bytestream_get_le32(&buf);
247 if(t < 0 || t > (1 << depth)){
248 av_log(avctx, AV_LOG_ERROR, "Incorrect number of colors - %X for bitdepth %d\n", t, depth);
253 buf = buf0 + 14 + ihsize; //palette location
254 if((hsize-ihsize-14) < (colors << 2)){ // OS/2 bitmap, 3 bytes per palette entry
255 for(i = 0; i < colors; i++)
256 ((uint32_t*)p->data[1])[i] = bytestream_get_le24(&buf);
258 for(i = 0; i < colors; i++)
259 ((uint32_t*)p->data[1])[i] = bytestream_get_le32(&buf);
263 if(comp == BMP_RLE4 || comp == BMP_RLE8){
265 p->data[0] += p->linesize[0] * (avctx->height - 1);
266 p->linesize[0] = -p->linesize[0];
268 ff_msrle_decode(avctx, (AVPicture*)p, depth, buf, dsize);
270 p->data[0] += p->linesize[0] * (avctx->height - 1);
271 p->linesize[0] = -p->linesize[0];
276 for (i = 0; i < avctx->height; i++) {
278 for (j = 0; j < n; j++) {
279 ptr[j*8+0] = buf[j] >> 7;
280 ptr[j*8+1] = (buf[j] >> 6) & 1;
281 ptr[j*8+2] = (buf[j] >> 5) & 1;
282 ptr[j*8+3] = (buf[j] >> 4) & 1;
283 ptr[j*8+4] = (buf[j] >> 3) & 1;
284 ptr[j*8+5] = (buf[j] >> 2) & 1;
285 ptr[j*8+6] = (buf[j] >> 1) & 1;
286 ptr[j*8+7] = buf[j] & 1;
294 for(i = 0; i < avctx->height; i++){
301 for(i = 0; i < avctx->height; i++){
303 for(j = 0; j < n; j++){
304 ptr[j*2+0] = (buf[j] >> 4) & 0xF;
305 ptr[j*2+1] = buf[j] & 0xF;
312 for(i = 0; i < avctx->height; i++){
313 const uint16_t *src = (const uint16_t *) buf;
314 uint16_t *dst = (uint16_t *) ptr;
316 for(j = 0; j < avctx->width; j++)
317 *dst++ = av_le2ne16(*src++);
324 for(i = 0; i < avctx->height; i++){
325 const uint8_t *src = buf;
328 for(j = 0; j < avctx->width; j++){
329 dst[0] = src[rgb[2]];
330 dst[1] = src[rgb[1]];
331 dst[2] = src[rgb[0]];
341 av_log(avctx, AV_LOG_ERROR, "BMP decoder is broken\n");
346 *picture = s->picture;
347 *data_size = sizeof(AVPicture);
352 static av_cold int bmp_decode_end(AVCodecContext *avctx)
354 BMPContext* c = avctx->priv_data;
356 if (c->picture.data[0])
357 avctx->release_buffer(avctx, &c->picture);
362 AVCodec ff_bmp_decoder = {
364 .type = AVMEDIA_TYPE_VIDEO,
366 .priv_data_size = sizeof(BMPContext),
367 .init = bmp_decode_init,
368 .close = bmp_decode_end,
369 .decode = bmp_decode_frame,
370 .capabilities = CODEC_CAP_DR1,
371 .long_name = NULL_IF_CONFIG_SMALL("BMP image"),