BMP image decoder

Originally committed as revision 4711 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavcodec/Makefile

@@ -197,8 +197,10 @@ endif
 ifeq ($(CONFIG_XL_DECODER),yes)
     OBJS+= xl.o
 endif
-      
-      
+ifeq ($(CONFIG_BMP_DECODER),yes)
+	OBJS+= bmp.o
+endif
+
 AMROBJS=
 ifeq ($(AMR_NB),yes)
 ifeq ($(AMR_NB_FIXED),yes)

libavcodec/allcodecs.c

@@ -518,6 +518,10 @@ void avcodec_register_all(void)
 #endif //CONFIG_ENCODERS
 #endif /* AMR_WB */
 
+#ifdef CONFIG_BMP_DECODER
+    register_avcodec(&bmp_decoder);
+#endif
+
     /* pcm codecs */
 #if defined (CONFIG_ENCODERS) && defined (CONFIG_DECODERS)
     #define PCM_CODEC(id, name) \

libavcodec/avcodec.h

@@ -112,6 +112,7 @@ enum CodecID {
     CODEC_ID_INDEO2,
     CODEC_ID_FRAPS,
     CODEC_ID_TRUEMOTION2,
+    CODEC_ID_BMP,
 
     /* various pcm "codecs" */
     CODEC_ID_PCM_S16LE= 0x10000,
@@ -2071,6 +2072,7 @@ extern AVCodec vorbis_decoder;
 extern AVCodec fraps_decoder;
 extern AVCodec libgsm_encoder;
 extern AVCodec libgsm_decoder;
+extern AVCodec bmp_decoder;
 
 /* pcm codecs */
 #define PCM_CODEC(id, name) \

libavcodec/bmp.c

+/*
+ * BMP image format
+ * Copyright (c) 2005 Mans Rullgard
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include "avcodec.h"
+#include "bitstream.h"
+#include "bswap.h"
+
+typedef struct BMPContext {
+    AVFrame picture;
+} BMPContext;
+
+#define BMP_RGB       0
+#define BMP_RLE8      1
+#define BMP_RLE4      2
+#define BMP_BITFIELDS 3
+
+#define read16(bits) bswap_16(get_bits(bits, 16))
+#define read32(bits) bswap_32(get_bits_long(bits, 32))
+
+static int bmp_decode_init(AVCodecContext *avctx){
+    BMPContext *s = avctx->priv_data;
+
+    avcodec_get_frame_defaults((AVFrame*)&s->picture);
+    avctx->coded_frame = (AVFrame*)&s->picture;
+
+    return 0;
+}
+
+static int bmp_decode_frame(AVCodecContext *avctx, 
+                            void *data, int *data_size,
+                            uint8_t *buf, int buf_size)
+{
+    BMPContext *s = avctx->priv_data;
+    AVFrame *picture = data;
+    AVFrame *p = &s->picture;
+    GetBitContext bits;
+    unsigned int fsize, hsize;
+    int width, height;
+    unsigned int depth;
+    unsigned int comp;
+    unsigned int ihsize;
+    int i, j, n, linesize;
+    uint32_t rgb[3];
+    uint8_t *ptr;
+    int dsize;
+
+    if(buf_size < 14){
+        av_log(avctx, AV_LOG_ERROR, "buf size too small (%d)\n", buf_size);
+        return -1;
+    }
+
+    init_get_bits(&bits, buf, buf_size);
+
+    if(get_bits(&bits, 16) != 0x424d){ /* 'BM' */
+        av_log(avctx, AV_LOG_ERROR, "bad magic number\n");
+        return -1;
+    }
+
+    fsize = read32(&bits);
+    if(buf_size < fsize){
+        av_log(avctx, AV_LOG_ERROR, "not enough data (%d < %d)\n",
+               buf_size, fsize);
+        return -1;
+    }
+
+    skip_bits(&bits, 16);       /* reserved1 */
+    skip_bits(&bits, 16);       /* reserved2 */
+
+    hsize = read32(&bits); /* header size */
+    if(fsize <= hsize){
+        av_log(avctx, AV_LOG_ERROR, "not enough data (%d < %d)\n",
+               fsize, hsize);
+        return -1;
+    }
+
+    ihsize = read32(&bits);       /* more header size */
+    if(ihsize + 14 > hsize){
+        av_log(avctx, AV_LOG_ERROR, "invalid header size %d\n", hsize);
+        return -1;
+    }
+
+    width = read32(&bits);
+    height = read32(&bits);
+
+    if(read16(&bits) != 1){ /* planes */
+        av_log(avctx, AV_LOG_ERROR, "invalid BMP header\n");
+        return -1;
+    }
+
+    depth = read16(&bits);
+
+    if(ihsize > 16)
+        comp = read32(&bits);
+    else
+        comp = BMP_RGB;
+
+    if(comp != BMP_RGB && comp != BMP_BITFIELDS){
+        av_log(avctx, AV_LOG_ERROR, "BMP coding %d not supported\n", comp);
+        return -1;
+    }
+
+    if(comp == BMP_BITFIELDS){
+        skip_bits(&bits, 20 * 8);
+        rgb[0] = read32(&bits);
+        rgb[1] = read32(&bits);
+        rgb[2] = read32(&bits);
+    }
+
+    avctx->codec_id = CODEC_ID_BMP;
+    avctx->width = width;
+    avctx->height = height > 0? height: -height;
+
+    avctx->pix_fmt = PIX_FMT_NONE;
+
+    switch(depth){
+    case 32:
+        if(comp == BMP_BITFIELDS){
+            rgb[0] = (rgb[0] >> 15) & 3;
+            rgb[1] = (rgb[1] >> 15) & 3;
+            rgb[2] = (rgb[2] >> 15) & 3;
+
+            if(rgb[0] + rgb[1] + rgb[2] != 3 ||
+               rgb[0] == rgb[1] || rgb[0] == rgb[2] || rgb[1] == rgb[2]){
+                break;
+            }
+        } else {
+            rgb[0] = 2;
+            rgb[1] = 1;
+            rgb[2] = 0;
+        }
+
+        avctx->pix_fmt = PIX_FMT_BGR24;
+        break;
+    case 24:
+        avctx->pix_fmt = PIX_FMT_BGR24;
+        break;
+    case 16:
+        if(comp == BMP_RGB)
+            avctx->pix_fmt = PIX_FMT_RGB555;
+        break;
+    default:
+        av_log(avctx, AV_LOG_ERROR, "depth %d not supported\n", depth);
+        return -1;
+    }
+
+    if(avctx->pix_fmt == PIX_FMT_NONE){
+        av_log(avctx, AV_LOG_ERROR, "unsupported pixel format\n");
+        return -1;
+    }
+
+    p->reference = 0;
+    if(avctx->get_buffer(avctx, p) < 0){
+        av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
+        return -1;
+    }
+    p->pict_type = FF_I_TYPE;
+    p->key_frame = 1;
+
+    buf += hsize;
+    dsize = buf_size - hsize;
+
+    n = avctx->width * (depth / 8);
+
+    if(n * avctx->height > dsize){
+        av_log(avctx, AV_LOG_ERROR, "not enough data (%d < %d)\n",
+               dsize, n * avctx->height);
+        return -1;
+    }
+
+    if(height > 0){
+        ptr = p->data[0] + (avctx->height - 1) * p->linesize[0];
+        linesize = -p->linesize[0];
+    } else {
+        ptr = p->data[0];
+        linesize = p->linesize[0];
+    }
+
+    switch(depth){
+    case 24:
+        for(i = 0; i < avctx->height; i++){
+            memcpy(ptr, buf, n);
+            buf += n;
+            ptr += linesize;
+        }
+        break;
+    case 16:
+        for(i = 0; i < avctx->height; i++){
+            uint16_t *src = (uint16_t *) buf;
+            uint16_t *dst = (uint16_t *) ptr;
+
+            for(j = 0; j < avctx->width; j++)
+                *dst++ = le2me_16(*src++);
+
+            buf += n;
+            ptr += linesize;
+        }
+        break;
+    case 32:
+        for(i = 0; i < avctx->height; i++){
+            uint8_t *src = buf;
+            uint8_t *dst = ptr;
+
+            for(j = 0; j < avctx->width; j++){
+                dst[0] = src[rgb[2]];
+                dst[1] = src[rgb[1]];
+                dst[2] = src[rgb[0]];
+                dst += 3;
+                src += 4;
+            }
+
+            buf += n;
+            ptr += linesize;
+        }
+        break;
+    default:
+        av_log(avctx, AV_LOG_ERROR, "BMP decoder is broken\n");
+        return -1;
+    }
+
+    *picture = s->picture;
+    *data_size = sizeof(AVPicture);
+
+    return buf_size;
+}
+
+AVCodec bmp_decoder = {
+    "bmp",
+    CODEC_TYPE_VIDEO,
+    CODEC_ID_BMP,
+    sizeof(BMPContext),
+    bmp_decode_init,
+    NULL,
+    NULL,
+    bmp_decode_frame
+};

libavformat/img2.c

@@ -51,6 +51,7 @@ static const IdStrMap img_tags[] = {
     { CODEC_ID_MPEG4     , "mpg4-img"},
     { CODEC_ID_FFV1      , "ffv1-img"},
     { CODEC_ID_RAWVIDEO  , "y"},
+    { CODEC_ID_BMP       , "bmp"},
     {0, NULL}
 };