3 * Copyright (c) 2005 Mans Rullgard
5 * This library is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU Lesser General Public
7 * License as published by the Free Software Foundation; either
8 * version 2 of the License, or (at your option) any later version.
10 * This library is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * Lesser General Public License for more details.
15 * You should have received a copy of the GNU Lesser General Public
16 * License along with this library; if not, write to the Free Software
17 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21 #include "bitstream.h"
24 typedef struct BMPContext {
31 #define BMP_BITFIELDS 3
33 #define read16(bits) bswap_16(get_bits(bits, 16))
34 #define read32(bits) bswap_32(get_bits_long(bits, 32))
36 static int bmp_decode_init(AVCodecContext *avctx){
37 BMPContext *s = avctx->priv_data;
39 avcodec_get_frame_defaults((AVFrame*)&s->picture);
40 avctx->coded_frame = (AVFrame*)&s->picture;
45 static int bmp_decode_frame(AVCodecContext *avctx,
46 void *data, int *data_size,
47 uint8_t *buf, int buf_size)
49 BMPContext *s = avctx->priv_data;
50 AVFrame *picture = data;
51 AVFrame *p = &s->picture;
53 unsigned int fsize, hsize;
58 int i, j, n, linesize;
64 av_log(avctx, AV_LOG_ERROR, "buf size too small (%d)\n", buf_size);
68 init_get_bits(&bits, buf, buf_size);
70 if(get_bits(&bits, 16) != 0x424d){ /* 'BM' */
71 av_log(avctx, AV_LOG_ERROR, "bad magic number\n");
75 fsize = read32(&bits);
77 av_log(avctx, AV_LOG_ERROR, "not enough data (%d < %d)\n",
82 skip_bits(&bits, 16); /* reserved1 */
83 skip_bits(&bits, 16); /* reserved2 */
85 hsize = read32(&bits); /* header size */
87 av_log(avctx, AV_LOG_ERROR, "not enough data (%d < %d)\n",
92 ihsize = read32(&bits); /* more header size */
93 if(ihsize + 14 > hsize){
94 av_log(avctx, AV_LOG_ERROR, "invalid header size %d\n", hsize);
98 width = read32(&bits);
99 height = read32(&bits);
101 if(read16(&bits) != 1){ /* planes */
102 av_log(avctx, AV_LOG_ERROR, "invalid BMP header\n");
106 depth = read16(&bits);
109 comp = read32(&bits);
113 if(comp != BMP_RGB && comp != BMP_BITFIELDS){
114 av_log(avctx, AV_LOG_ERROR, "BMP coding %d not supported\n", comp);
118 if(comp == BMP_BITFIELDS){
119 skip_bits(&bits, 20 * 8);
120 rgb[0] = read32(&bits);
121 rgb[1] = read32(&bits);
122 rgb[2] = read32(&bits);
125 avctx->codec_id = CODEC_ID_BMP;
126 avctx->width = width;
127 avctx->height = height > 0? height: -height;
129 avctx->pix_fmt = PIX_FMT_NONE;
133 if(comp == BMP_BITFIELDS){
134 rgb[0] = (rgb[0] >> 15) & 3;
135 rgb[1] = (rgb[1] >> 15) & 3;
136 rgb[2] = (rgb[2] >> 15) & 3;
138 if(rgb[0] + rgb[1] + rgb[2] != 3 ||
139 rgb[0] == rgb[1] || rgb[0] == rgb[2] || rgb[1] == rgb[2]){
148 avctx->pix_fmt = PIX_FMT_BGR24;
151 avctx->pix_fmt = PIX_FMT_BGR24;
155 avctx->pix_fmt = PIX_FMT_RGB555;
158 av_log(avctx, AV_LOG_ERROR, "depth %d not supported\n", depth);
162 if(avctx->pix_fmt == PIX_FMT_NONE){
163 av_log(avctx, AV_LOG_ERROR, "unsupported pixel format\n");
168 if(avctx->get_buffer(avctx, p) < 0){
169 av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
172 p->pict_type = FF_I_TYPE;
176 dsize = buf_size - hsize;
178 n = avctx->width * (depth / 8);
180 if(n * avctx->height > dsize){
181 av_log(avctx, AV_LOG_ERROR, "not enough data (%d < %d)\n",
182 dsize, n * avctx->height);
187 ptr = p->data[0] + (avctx->height - 1) * p->linesize[0];
188 linesize = -p->linesize[0];
191 linesize = p->linesize[0];
196 for(i = 0; i < avctx->height; i++){
203 for(i = 0; i < avctx->height; i++){
204 uint16_t *src = (uint16_t *) buf;
205 uint16_t *dst = (uint16_t *) ptr;
207 for(j = 0; j < avctx->width; j++)
208 *dst++ = le2me_16(*src++);
215 for(i = 0; i < avctx->height; i++){
219 for(j = 0; j < avctx->width; j++){
220 dst[0] = src[rgb[2]];
221 dst[1] = src[rgb[1]];
222 dst[2] = src[rgb[0]];
232 av_log(avctx, AV_LOG_ERROR, "BMP decoder is broken\n");
236 *picture = s->picture;
237 *data_size = sizeof(AVPicture);
242 AVCodec bmp_decoder = {