1
0
mirror of https://github.com/mpv-player/mpv synced 2024-12-13 02:15:59 +00:00
mpv/libmpdemux/demux_bmp.c

117 lines
3.3 KiB
C
Raw Normal View History

/*
BMP file parser for the MPlayer program
by Mike Melanson
*/
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include "config.h"
#include "mp_msg.h"
#include "help_mp.h"
#include "stream.h"
#include "demuxer.h"
#include "stheader.h"
typedef struct {
int image_size;
int image_offset;
} bmp_image_t;
// Check if a file is a BMP file depending on whether starts with 'BM'
int bmp_check_file(demuxer_t *demuxer)
{
if (stream_read_word(demuxer->stream) == (('B' << 8) | 'M'))
return 1;
else
return 0;
}
// return value:
// 0 = EOF or no stream found
// 1 = successfully read a packet
int demux_bmp_fill_buffer(demuxer_t *demuxer)
{
bmp_image_t *bmp_image = (bmp_image_t *)demuxer->priv;
stream_reset(demuxer->stream);
stream_seek(demuxer->stream, bmp_image->image_offset);
ds_read_packet(demuxer->video, demuxer->stream, bmp_image->image_size,
0, bmp_image->image_offset, 1);
return 1;
}
demuxer_t* demux_open_bmp(demuxer_t* demuxer)
{
sh_video_t *sh_video = NULL;
unsigned int filesize;
unsigned int data_offset;
bmp_image_t *bmp_image;
// go back to the beginning
stream_reset(demuxer->stream);
stream_seek(demuxer->stream, 2);
filesize = stream_read_dword_le(demuxer->stream);
stream_skip(demuxer->stream, 4);
data_offset = stream_read_word_le(demuxer->stream);
stream_skip(demuxer->stream, 2);
// create a new video stream header
sh_video = new_sh_video(demuxer, 0);
// make sure the demuxer knows about the new video stream header
demuxer->video->sh = sh_video;
// make sure that the video demuxer stream header knows about its
// parent video demuxer stream
sh_video->ds = demuxer->video;
// load the BITMAPINFOHEADER
// allocate size and take the palette table into account
sh_video->bih = (BITMAPINFOHEADER *)malloc(data_offset - 12);
sh_video->bih->biSize = stream_read_dword_le(demuxer->stream);
sh_video->bih->biWidth = stream_read_dword_le(demuxer->stream);
sh_video->bih->biHeight = stream_read_dword_le(demuxer->stream);
sh_video->bih->biPlanes = stream_read_word_le(demuxer->stream);
sh_video->bih->biBitCount = stream_read_word_le(demuxer->stream);
sh_video->bih->biCompression = stream_read_dword_le(demuxer->stream);
sh_video->bih->biSizeImage = stream_read_dword_le(demuxer->stream);
sh_video->bih->biXPelsPerMeter = stream_read_dword_le(demuxer->stream);
sh_video->bih->biYPelsPerMeter = stream_read_dword_le(demuxer->stream);
sh_video->bih->biClrUsed = stream_read_dword_le(demuxer->stream);
sh_video->bih->biClrImportant = stream_read_dword_le(demuxer->stream);
// fetch the palette
stream_read(demuxer->stream, (unsigned char *)(sh_video->bih) + 40,
sh_video->bih->biClrUsed * 4);
// load the data
bmp_image = (bmp_image_t *)malloc(sizeof(bmp_image_t));
bmp_image->image_size = filesize - data_offset;
bmp_image->image_offset = data_offset;
// custom fourcc for internal MPlayer use
sh_video->format = sh_video->bih->biCompression;
sh_video->disp_w = sh_video->bih->biWidth;
sh_video->disp_h = sh_video->bih->biHeight;
// get the speed
sh_video->fps = 2;
sh_video->frametime = 1 / sh_video->fps;
demuxer->priv = bmp_image;
return demuxer;
}
void demux_close_bmp(demuxer_t* demuxer) {
bmp_image_t *bmp_image = demuxer->priv;
if(!bmp_image)
return;
free(bmp_image);
}