rxbag (Boxturtle) has this functionality for individual frames.  From the wiki:

Right-clicking on the image opens a context menu which allows you to resize the window to the original resolution, or save the image to a .png file.

rxbag (C-turtle) will allow exporting multiple frames.

Tim

On Mon, May 31, 2010 at 4:37 AM, Victor Eruhimov <relrotciv@googlemail.com> wrote:
There is extract_images node in image_view that does exactly the same as image_view node, but instead of showing an image it saves it to a jpg file. I believe Patrick wrote image_saver (also in image_view) that does something similar. I suggest this functionality should reside somewhere in rxbag.

Best Regards, Victor

On May 31, 2010, at 10:05 AM, Kurt Konolige wrote:

> Hmm, that's a little old, and only works for the old topic "raw_stereo",
> which doesn't exist in current ROS.  I can probably munge it to work
> with new topics, though.
>
> Cheers --Kurt
>
> On 5/30/2010 9:09 PM, Jeremy Leibs wrote:
>> I have not used it, but there is a script called "bag2png.py" in
>> rosrecord.  I expect it will do what you want.
>>
>> On Sun, May 30, 2010 at 9:06 PM, Kurt Konolige
>> <konolige@willowgarage.com>  wrote:
>>> Sorry if this has already been covered -
>>>
>>> Any way to take the images from a bag file and put them into normal
>>> PNG-type files in a directory?
>>>
>>> Cheers --Kurt
>>> _______________________________________________
>>> ros-users mailing list
>>> ros-users@code.ros.org
>>> https://code.ros.org/mailman/listinfo/ros-users
>>>
>> _______________________________________________
>> ros-users mailing list
>> ros-users@code.ros.org
>> https://code.ros.org/mailman/listinfo/ros-users
>>
> _______________________________________________
> ros-users mailing list
> ros-users@code.ros.org
> https://code.ros.org/mailman/listinfo/ros-users

_______________________________________________
ros-users mailing list
ros-users@code.ros.org
https://code.ros.org/mailman/listinfo/ros-users