Tryst with video recording.

Shooting a movie for the Doofus game turned out to be more than a headache; a bad case of migraine I must say. Well it all began soon after releasing the game. The logical next step was to shoot a movie/video to put on Youtube. What was supposed to be a 2 hour job turned out to be a lot harder than I had anticipated. Most screencap utilities do a pretty good job at capturing screen movies, however, what I failed to realize is the fact that most of them are hopeless when capturing any Direct3D or OpenGL rendered visuals withing a game. I am extremely disappointed with capture software that is available for recording an in-game movie. I tried several applications that are available, both free and commercial ones, but all of them turned out to be poor — either extremely slow or extremely buggy.

In the end I had to manually write an AVI capture facility into the engine code; ie. physically get the Back-buffer, StretctRect it into a texture, download it off the GPU and  store it’s contents into an AVI file via a bitmap, frame by frame. Similarly with the music and game sounds, for which I had to code in wave capture in OpenAL. Whew done! Unfortunately not all went as planned. I soon realized that the video and audio streams in the recorded AVI file went completely out of sync. That’s because the game’s frame-rate varies considerably while playing, whereas the sound is always played at the same rate. The problem unfortunately is — unlike the game the AVI file’s frame-rate is always fixed. So after a 1 min shoot, I could clearly notice a mismatch in video and sound. I tried unsuccessfully to correct the problem, but the problem still persists. That said, at least the results of  video capture were better than any 3rd party application I had tried before. So it wasn’t a total waste of time.

So yeah, I could shoot video clips, albeit not as good as I would have liked. I wanted a 1024×768 res video and all I could manage was a 640×480 one at pretty moderate quality given that all the streaming was done into a MPG4 compressed stream and there was a noticeable loss in quality. Then came the next challenge; editing the video into a full streaming movie. Movie maker was a the only free option available and the app is not too difficult to use. However, the app encodes videos only in WMA format and I couldn’t locate a MPG , AVI or an FLV option.  That meant I needed to convert the movie to a flash movie (FLV) so it could be streamed off the Internet using a SWF flash plugin. Bah! WTF! Well it turns out ffmpeg can re-encode movie files to most formats; including FLV and it’s free. Thank you ffmpeg.

Then it was Youtube. Well it seems when you upload a video to Youtube the server converts and re-encodes the uploaded video file using a really poor quality compression. I am not sure which format the FLV encoder on Youtube uses, but the results turned out to be a blocky pixelated mess. I guess, after some many conversion and switching formats, the video quality on Youtube turned out to be pretty poor. You can compare the quality with the ones on the Doofus website (the larger one here) and  you will understand what I mean.

Bah! The next time I am directly streaming content into a external HD video recorder via the TV-out option of the video card to avoid such craziness!

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