[FFmpeg-user] piping images into ffmpeg

[Akilan R]

Hi,

I have a C program which generates a series of images and I wanted to make
them into a video which should be streamed in real time or stored in a file.
While reading up ffmpeg documentation I came across repeatedly that ffmpeg
can take input from named pipes.

My question is in what format should the files given into the pipe should be
and how to input the files into the pipe.

I tried this:

$ cat hello-*.ppm | ffmpeg -f image2pipe -vcodec ppm -r 25 -i pipe: -r 25
output.mp4

but video was bad. (Here the input comes from already stored files as i was
testing; once it works i'll pipe in output from my program like this or
using named pipes.)
There is no problem with image files as this one worked flawlessly:

$ ffmpeg -f image2 -r 25 -i hello-%03d.ppm -r 25 output.mp4

[Tim Nicholson]

Post by Akilan R
Hi,
I have a C program which generates a series of images and I wanted to make
them into a video which should be streamed in real time or stored in a file.
While reading up ffmpeg documentation I came across repeatedly that ffmpeg
can take input from named pipes.
My question is in what format should the files given into the pipe should be
and how to input the files into the pipe.
$ cat hello-*.ppm | ffmpeg -f image2pipe -vcodec ppm -r 25 -i pipe: -r 25
output.mp4
but video was bad. (Here the input comes from already stored files as i was
testing; once it works i'll pipe in output from my program like this or
using named pipes.)
$ ffmpeg -f image2 -r 25 -i hello-%03d.ppm -r 25 output.mp4

Err, if "-f image2" is correct then why change it to "-f image2pipe" ?

What does something like:-

$ cat hello-*.ppm | ffmpeg -f image2 -r 25 -i pipe: -r 25 output.mp4

do?

I think image2pipe is more for output formatting. yuv4mpegpipe certainly is.

[Akilan R]

Post by Tim Nicholson
Err, if "-f image2" is correct then why change it to "-f image2pipe" ?

image2 is correct for getting input from consecutively numbered files.
image2pipe is for getting from pipe.

Post by Tim Nicholson
I think image2pipe is more for output formatting. yuv4mpegpipe certainly is.

Don't read '2pipe' as 'to pipe'; notice that first option also has 2 in the
end. :-)