We recently had a question come in about how to quickly assemble image sequences into an AVI. Here’s the way I prefer to do it on Windows. It uses free, open source software, Virtual Dub, and is very quick.
Getting Virtual Dub
This will download as a .zip file. Open the .zip file and extract all of its contents:
Converting an Image Sequence
Now, choose File -> Open from the menu, or hit Ctrl+O. This will give you the almost completely normal File Open dialog. I say “almost,” because this one has two extra check boxes at the bottom: “Ask for extended options after this dialog,” and “Automatically load linked segments.” We only really care about the second one for this tutorial. Choose the first image in your sequence, and make sure the “Automatically load linked segments” checkbox is checked.
VirtualDub will now look something like this (although, of course, with your image sequence, shown, not mine).
Next, we need to make sure the frame rate is correct. Choose Video->Frame Rate from the menu, and tweak the settings there:
If you like, you can choose a codec by going to Video->Compression. Be aware that some codecs are lossy. Search for info on the codecs on your system, and choose according to your needs. If you’re going to do further editing, it’s generally best to choose a lossless codec. If you’re just dumping this to a file you’re going to post for a quick client review, I recommend XVid – it’s free and provides very good compression ratios.
Next, choose File->Save As AVI from the menu, or just hit F7.
Choose the name of your output .avi file:
And VirtualDub will immediately begin converting your image sequence to .avi:
Tips and Tricks
If you have exceptionally long sequences, turning off “Show Input Video” and/or “Show Output Video” in the conversion status window (see last sceenshot) will increase the speed of conversion.
If you have a lot of sequences to convert, you can choose “File->Queue Batch Operation->Save As AVI,” or hit Ctrl+Shift+F7, to build a queue of conversions. Once your queue is deep enough, go to “File->Job Control” or hit F4 to start converting all of the sequences.
VirtualDub is capable of a lot more than just converting image sequences into AVI’s. You can load AVI’s and save them to different codecs, convert AVI’s into animated .gif’s, replace the audio in an AVI, copy individual frames from an AVI, and even use it with the cryptic but very powerful AVISynth toolkit to do scripted video editing.
We’ve gone through one way to convert image sequences to AVI’s. There are probably dozens or hundreds available. There are command-line utilities to do this, GUI applications that do a lot more than Virtual Dub, Mac and Linux applications. Which do you use? What questions about this approach do you have?