extract_images dropping frames

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Dear All

I have noticed that when I used the extract_images in image_view pkg to extract images from a bag file, it drops frames.

Even if I set the "sec_per_frame" close to zero like 0.0000000000001 or modify the code that do not consider delay in line : if(delay >= sec_per_frame_)

still the number of frames which is extracted is less than the actual recorded frames ?

I noticed this by extracting the header information directly from a bag file and find the number of frames in bag file is greater than number of frames from extract_images.

I appreciate your help.