2 * BMP image format decoder
3 * Copyright (c) 2005 Mans Rullgard
5 * This file is part of FFmpeg.
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.
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.
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
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,
38 const uint8_t *buf, int buf_size)
40 BMPContext *s = avctx->priv_data;
41 AVFrame *picture = data;
42 AVFrame *p = &s->picture;
43 unsigned int fsize, hsize;
48 int i, j, n, linesize;
52 const uint8_t *buf0 = buf;
55 av_log(avctx, AV_LOG_ERROR, "buf size too small (%d)\n", buf_size);
59 if(bytestream_get_byte(&buf) != 'B' ||
60 bytestream_get_byte(&buf) != 'M') {
61 av_log(avctx, AV_LOG_ERROR, "bad magic number\n");
65 fsize = bytestream_get_le32(&buf);
67 av_log(avctx, AV_LOG_ERROR, "not enough data (%d < %d)\n",
72 buf += 2; /* reserved1 */
73 buf += 2; /* reserved2 */
75 hsize = bytestream_get_le32(&buf); /* header size */
77 av_log(avctx, AV_LOG_ERROR, "not enough data (%d < %d)\n",
82 ihsize = bytestream_get_le32(&buf); /* more header size */
83 if(ihsize + 14 > hsize){
84 av_log(avctx, AV_LOG_ERROR, "invalid header size %d\n", hsize);
89 width = bytestream_get_le32(&buf);
90 height = bytestream_get_le32(&buf);
91 } else if (ihsize == 12) {
92 width = bytestream_get_le16(&buf);
93 height = bytestream_get_le16(&buf);
95 av_log(avctx, AV_LOG_ERROR, "unsupported BMP file, patch welcome\n");
99 if(bytestream_get_le16(&buf) != 1){ /* planes */
100 av_log(avctx, AV_LOG_ERROR, "invalid BMP header\n");
104 depth = bytestream_get_le16(&buf);
107 comp = bytestream_get_le32(&buf);
111 if(comp != BMP_RGB && comp != BMP_BITFIELDS && comp != BMP_RLE4 && comp != BMP_RLE8){
112 av_log(avctx, AV_LOG_ERROR, "BMP coding %d not supported\n", comp);
116 if(comp == BMP_BITFIELDS){
118 rgb[0] = bytestream_get_le32(&buf);
119 rgb[1] = bytestream_get_le32(&buf);
120 rgb[2] = bytestream_get_le32(&buf);
123 avctx->width = width;
124 avctx->height = height > 0? height: -height;
126 avctx->pix_fmt = PIX_FMT_NONE;
130 if(comp == BMP_BITFIELDS){
131 rgb[0] = (rgb[0] >> 15) & 3;
132 rgb[1] = (rgb[1] >> 15) & 3;
133 rgb[2] = (rgb[2] >> 15) & 3;
135 if(rgb[0] + rgb[1] + rgb[2] != 3 ||
136 rgb[0] == rgb[1] || rgb[0] == rgb[2] || rgb[1] == rgb[2]){
145 avctx->pix_fmt = PIX_FMT_BGR24;
148 avctx->pix_fmt = PIX_FMT_BGR24;
152 avctx->pix_fmt = PIX_FMT_RGB555;
153 if(comp == BMP_BITFIELDS)
154 avctx->pix_fmt = rgb[1] == 0x07E0 ? PIX_FMT_RGB565 : PIX_FMT_RGB555;
157 if(hsize - ihsize - 14 > 0)
158 avctx->pix_fmt = PIX_FMT_PAL8;
160 avctx->pix_fmt = PIX_FMT_GRAY8;
163 if(hsize - ihsize - 14 > 0){
164 avctx->pix_fmt = PIX_FMT_PAL8;
166 av_log(avctx, AV_LOG_ERROR, "Unknown palette for 16-colour BMP\n");
171 avctx->pix_fmt = PIX_FMT_MONOBLACK;
174 av_log(avctx, AV_LOG_ERROR, "depth %d not supported\n", depth);
178 if(avctx->pix_fmt == PIX_FMT_NONE){
179 av_log(avctx, AV_LOG_ERROR, "unsupported pixel format\n");
184 avctx->release_buffer(avctx, p);
187 if(avctx->get_buffer(avctx, p) < 0){
188 av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
191 p->pict_type = FF_I_TYPE;
195 dsize = buf_size - hsize;
197 /* Line size in file multiple of 4 */
198 n = ((avctx->width * depth) / 8 + 3) & ~3;
200 if(n * avctx->height > dsize && comp != BMP_RLE4 && comp != BMP_RLE8){
201 av_log(avctx, AV_LOG_ERROR, "not enough data (%d < %d)\n",
202 dsize, n * avctx->height);
206 // RLE may skip decoding some picture areas, so blank picture before decoding
207 if(comp == BMP_RLE4 || comp == BMP_RLE8)
208 memset(p->data[0], 0, avctx->height * p->linesize[0]);
210 if(depth == 4 || depth == 8)
211 memset(p->data[1], 0, 1024);
214 ptr = p->data[0] + (avctx->height - 1) * p->linesize[0];
215 linesize = -p->linesize[0];
218 linesize = p->linesize[0];
221 if(avctx->pix_fmt == PIX_FMT_PAL8){
222 buf = buf0 + 14 + ihsize; //palette location
223 if((hsize-ihsize-14)>>depth < 4){ // OS/2 bitmap, 3 bytes per palette entry
224 for(i = 0; i < (1 << depth); i++)
225 ((uint32_t*)p->data[1])[i] = bytestream_get_le24(&buf);
227 for(i = 0; i < (1 << depth); i++)
228 ((uint32_t*)p->data[1])[i] = bytestream_get_le32(&buf);
232 if(comp == BMP_RLE4 || comp == BMP_RLE8){
233 ff_msrle_decode(avctx, p, depth, buf, dsize);
237 for(i = 0; i < avctx->height; i++){
244 for(i = 0; i < avctx->height; i++){
246 for(j = 0; j < n; j++){
247 ptr[j*2+0] = (buf[j] >> 4) & 0xF;
248 ptr[j*2+1] = buf[j] & 0xF;
255 for(i = 0; i < avctx->height; i++){
256 memcpy(ptr, buf, avctx->width);
262 for(i = 0; i < avctx->height; i++){
263 memcpy(ptr, buf, avctx->width*(depth>>3));
269 for(i = 0; i < avctx->height; i++){
270 const uint16_t *src = (const uint16_t *) buf;
271 uint16_t *dst = (uint16_t *) ptr;
273 for(j = 0; j < avctx->width; j++)
274 *dst++ = le2me_16(*src++);
281 for(i = 0; i < avctx->height; i++){
282 const uint8_t *src = buf;
285 for(j = 0; j < avctx->width; j++){
286 dst[0] = src[rgb[2]];
287 dst[1] = src[rgb[1]];
288 dst[2] = src[rgb[0]];
298 av_log(avctx, AV_LOG_ERROR, "BMP decoder is broken\n");
303 *picture = s->picture;
304 *data_size = sizeof(AVPicture);
309 static av_cold int bmp_decode_end(AVCodecContext *avctx)
311 BMPContext* c = avctx->priv_data;
313 if (c->picture.data[0])
314 avctx->release_buffer(avctx, &c->picture);
319 AVCodec bmp_decoder = {
328 .long_name = NULL_IF_CONFIG_SMALL("BMP image"),