[gimp] crop/cut something out of an image #2

**FakeOutdoorsman** · October 16th, 2015

This is a continuation of the closed thread [gimp] crop/cut something out of an image. I didn't get why it was closed, but it prevented me from providing a more efficient answer. I attempted to contact the moderator who closed the thread and received no reply, and also received no reply in #ubuntuforums. (So go ahead and merge if you like).

The question:

Originally Posted by joe.koenig

I can't seem to be able to perform one single, simple task: cut/crop a portion from the middle of an image. Just a portion in the middle the picture. I.e: Imagine a pictiue. Divide it into three vertically equally sized parts. Cut/crop the middle part out and make a new picture of the two remaining fragments.

This can be done with a single command using ffmpeg for any sized image or video:

Code:

ffmpeg -i input -filter_complex "[0:v]crop=iw:ih/3:0:0[top];[0:v]crop=iw:ih/3:0:ih-oh[bot];[top][bot]vstack" output

If your ffmpeg is too old for the vstack filter, then simply download a recent build (also see how to use).

**shantiq** · October 16th, 2015

so cool Fake how would you modify the syntax here [i tried and failed] to divide crop and splice horizontally [the other way] ?

**coldraven** · October 16th, 2015

Originally Posted by shantiq

so cool Fake how would you modify the syntax here [i tried and failed] to divide crop and splice horizontally [the other way] ?

FakeOutdoorsman is the Chuck Norris of the ffmpeg world! Not only can he chop down mountains but he uses ffmpeg to butter his toast in the mornings

Maybe we should start a separate thread on this theme

**shantiq** · October 16th, 2015

[+1]Yes Cold Bird maybe we are a smidgeon off topic but then again maybe not as praise and gratefulness cannot be out of topic ... for he is a Master

Yes he is that good he probably could run a dating site with it :]

PS and to be back in topic i tried twelve or thirteen permutations to get the horizontal cut worked out but hey I need a masterclass here; so we await with bated breath .... please tell us Great FF and thank you!

PS2 [only for comedy lovers]
Some say there is even an ffmpeg command which might allow one to walk on H₂O

**FakeOutdoorsman** · October 17th, 2015

Originally Posted by shantiq

so cool Fake how would you modify the syntax here [i tried and failed] to divide crop and splice horizontally [the other way] ?

I find breaking up the command so each filterchain is on its own line makes filtering easier to follow:

Code:

ffmpeg -i input -filter_complex \
"[0:v]crop=iw/3:ih:0:0[l]; \
 [0:v]crop=iw/3:ih:iw-ow:0[r]; \
 [l][r]hstack" \
output

The 4 colon separated parts of crop consist of:

Code:

crop=width:height:x position:y position

Imagine a 640x480 input. The second crop in the example:

Code:

crop=iw/3:ih:iw-ow:0

would be the same as:

Code:

crop=640/3:480:640-(640/3):0

which is the same as (approximately since I rounded):

Code:

crop=213:480:426:0

From the 640x480 sized input this will make a 213x480 sized output. The 426 means the starting position from the crop will be 426 pixels over to the right.

See the crop filter documentation for info on each of those options.

Originally Posted by coldraven

...he uses ffmpeg to butter his toast in the mornings

Thank you for the kind words, but butter sometimes gives me gas. To borrow andrew.46's signature:

Originally Posted by Morpheus

You think that's air you're breathing now?

Originally Posted by shantiq

...he probably could run a dating site with it :]

"Likes: filtergraphs, stream specifiers, muxing."

Ladies, please form an orderly queue.

**shantiq** · October 17th, 2015

Thanx Fake no wonder I was short of the mark :] great explanations
This is TRULY astounding software !

Ps: also entered in my terminal ffmpeg -i EurasianPrincess -i MiddleAgedFrenchDude --"Likes: filtergraphs, stream specifiers, muxing" BlissfulCouple.mkv

Will report :]