Attachment_fu

Hello,
I have a functionality where i need to upload an image, So for that i am
using attachment_fu + acts_as_state_machine,. and every thing is
working
fine. But now from the view front i want to display as an thumbnail
image
just like youtube but the problem is that how do i crop a image from a
video?

Thanks for any help

Thanks
Abhis

Abhishek shukla wrote:

Hello,
I have a functionality where i need to upload an image, So for that i am
using attachment_fu + acts_as_state_machine,. and every thing is
working
fine. But now from the view front i want to display as an thumbnail
image
just like youtube but the problem is that how do i crop a image from a
video?

Is your question on actually getting a frame from a video file, or
cropping an image?

As far as grabbing a frame that might depend on what video format you’re
using. For example QuickTime provides methods for getting/setting a
poster frame. So from the Quicktime API you would use a message to
QTMovie:

  • (NSImage *)posterImage.

In case no posterImage has been set then you could fall back to getting
some other frame using the message:

  • (NSImage *)frameImageAtTime:(QTTme)time

Now, obviously that’s the internals of QuickTime, but the point I’m
making is that I’m not sure that attachement_fu itself is going to help
you. I’m sure there is probably an open source tool that can provide
access to these features.

Maybe ffmpeg would help:
http://ffmpeg.org/

Robert W. wrote:

Maybe ffmpeg would help:
http://ffmpeg.org/

An excerpt from the ffmpeg docs:

For extracting images from a video:

ffmpeg -i foo.avi -r 1 -s WxH -f image2 foo-%03d.jpeg

This will extract one video frame per second from the video and will
output them in files named foo-001.jpeg',foo-002.jpeg’, etc. Images
will be rescaled to fit the new WxH values.

If you want to extract just a limited number of frames, you can use the
above command in combination with the -vframes or -t option, or in
combination with -ss to start extracting from a certain point in time.


-ss position' Seek to given time position in seconds. hh:mm:ss[.xxx] syntax is also supported. ... ...-vframes number’
Set the number of video frames to record.

This looks to me like it should work well for your needs.

Thanks robert for sharing the ideas will defiantly implement it.

On Thu, Sep 24, 2009 at 8:54 PM, Robert W. <

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