How to convert a video file into an animated GIF in Photoshop?
I was trying to convert an MP4 into an animated GIF for an answer on here.
I tried opening the file directly in Photoshop, and then clicking on the timeline menu and choosing both:
Convert Frames → Flatten Frames into Clips and
Convert Frames → Convert to Frame Animation
But neither of them worked. They appeared to just flatten it into a single image.
How can I create an animated GIF from a video file in Adobe Photoshop?
To Convert the Video File into a Compatible Structure for the Animated GIF File Format
Open Photoshop without opening the video file.
Go to File → Import → Video Frames to Layers.
In the options that appear, make sure the "Make Frame Animation" checkbox is ticked.
At this stage you can also select only a specified range of the video and only import every 2nd, 3rd, 4th, nth frame. Useful for many reasons, the most obvious being to reduce file size.
To Save / Output an Animated GIF from the Generated Frames
Go to File → Save for Web... (or File → Export → Save for Web (Legacy)... in newer versions)
Choose one of the GIF options from the preset menu, or choose the GIF option in the dropdown list underneath the presets and adjust the options based on your needs.
Click "Save", give it a name, and enjoy.