[linux-dvb] I found a way to display still .jpg and .ppm s on the TV

[Marcus O.C. Metzler <mocm@convergence.de>]

Jan Panteltje writes:
 > Maybe all of you already figured this out.
 > the way I am doing it is a bit complicated:
 > 
 > I have: xx.jpg
 > Then I resize it with 'display' (part of imagemagick) to 352x288
 > Nwxt convert it to .ppm with djpeg -pnm xx.jpg >frame.1.ppm
 > 
 > Make a special parameter file for mpeg_encode (for just frame.1.ppm)
 > mpeg_encode single-frame.param
 > This results in (for example) movie.mpg (VERY short)
 > 
 > Then I wrote a very small C program that sends the movie.mpg 
 > REPEATEDLY to /dev/video
 >  (without closing that device)

Are you aware that there is a call in the DVB API where you can send
an I-frame to be displayed as a still picture?

So you could do something like this:

int videoStillPicture(int fd, struct videoDisplayStillPicture *sp)
{
	int ans;

	if ( (ans = ioctl(fd,VIDEO_STILLPICTURE, sp) < 0)){
		perror("VIDEO STILLPICTURE: ");
		return -1;
	}

	return 0;
}

void load_iframe(int filefd, int fd)
{
	struct stat st;
	struct videoDisplayStillPicture sp;

	fstat(filefd, &st);
	
	sp.iFrame = (char *) malloc(st.st_size);
	sp.size = st.st_size;
	printf("I-frame size: %d\n", sp.size);
	
	if(!sp.iFrame) {
		printf("No memory for I-Frame\n");
		return;
	}

	printf("read: %d bytes\n",read(filefd,sp.iFrame,sp.size));
	videoStillPicture(fd,&sp);

	sleep(3); //hold picture for 3 secs and then start replay again
	videoPlay(fd);
}

main(int argc, char **argv)
{
	int fd;
	int filefd;

	if (argc < 2) return -1;

	if ( (filefd = open(argv[1],O_RDONLY)) < 0){
		perror("File open:");
		return -1;
	}
	if((fd = open("/dev/ost/video",O_RDWR|O_NONBLOCK)) < 0){
		perror("VIDEO DEVICE: ");
		return -1;
	}

	load_iframe(filefd, fd);
	play_file_video(filefd, fd);
	close(fd);
	close(filefd);
	return 0;
}



Marcus

---------------------------------------------------------------------
Dr. Marcus Metzler                             
mocm@netcologne.de                     http://www.metzlerbros.de
mocm@convergence.de                    http://www.convergence.de

Convergence Integrated Media GmbH          
Rosenthaler Str. 51                   
D-10178 Berlin                             
---------------------------------------------------------------------


--- 
Info:
To unsubscribe send a mail to listar@linuxtv.org with "unsubscribe linux-dvb" as subject.