Downsizing from HD to SD

[k93]

I have some video files that are in HD (720p and above) quality. I would like downsize these to SD quality, mainly for size reasons (I don't mind viewing video in SD quality). Typically this would be from 1280x720 to 720x404 with all other settings the same. What would be the best software and process/settings to do this?

I am using an older MacPro (OSX 10.6.8). Handbrake is the software that first comes to mind, but there may be other software that would be more suitable.

[Baldrick]

Handbrake is very good for this.

If you want some basic editing(cutting) could you use mpeg streamclip or avidemux. Convert to mp4 with h264/avc video.

[Tom Saurus]

k03: I use Vidcoder which is based on Handbrake. I understand your viewpoint of going for a smaller file size. I was going to upgrade to a Blu ray burner but I am no longer confident in that type of media and beyond that the cost of keeping up with that is beyond my meager income. I will figure out some presets for you. I think for the first little while keep you original files and experiment with downsizing to 480i and 380 i unless you started with progressive to begin with. There is a technique to convert interlaced to progressive that may be of interest. You have to find out what is the most acceptable picture for you at a smaller size.

[Tom Saurus]

k93: 720 x 404 is perhaps the best dimensions. I quite often use Vidcoder to crop an SD capture that has a black box all the way around the video and after the crop have it fit in the 720 x 480 dimensions. The videos usually turn out quite well depending on the CQ number I chose. If your video is already 16:9 you don't have to crop. I will have to do some screencap pictures to show you how to make a preset so that you just have to select that preset for the job and since you can do batch jobs with Vidcoder you can set it and go. Be warned though Vidcoder is pretty CPU intensive. If your videos are 4:3 there is no reason to crop you will just have the black bars on the side that you started with by not cropping. I better do those screencaps soon. Hopefully there is a version of Vidcoder for the Mac.

[Tom Saurus]

I forgot to mention there is a preview mode in Vidcoder where you can have Vidcoder encode perhaps a 30 or 60 second clip that you can use to judge how the whole encode would turn out. I find it comes it mighty handy to have the option to preview things to see the quality of the video and audio to see if it is good enough.

[hello_hello]

k93: 720 x 404 is perhaps the best dimensions.

I'd use 704x396 myself as it's exactly 16:9 and there won't be a noticeable quality difference between that and 720x404, which isn't quite 16:9. It's an OCD thing.....

[Tom Saurus]

k93: 720 x 404 is perhaps the best dimensions.

I'd use 704x396 myself as it's exactly 16:9 and there won't be a noticeable quality difference between that and 720x404, which isn't quite 16:9. It's an OCD thing.....

hello_hello: I am doing a test encode right now with the specs you wrote about. Thank you it is nice to learn new things.

[Tom Saurus]

k93: Only you can judge what is acceptable when it comes to video and audio quality. I find that setting the CQ to 18 gives you a file nearly as good as the original. A CQ of 20 is pretty acceptable as well, and results in some savings when it comes to file size. I find to that re-encoding the audio do let's say stereo 128 kbs saves some size as well if it originally was recorded at at over 300 kbs. You also have the option of passing through the audio. It sometimes takes a bit of experimenting once you get comfortable with Vidcoder. Also make note it is best to go with CQ because it adapts itself to the amount of action in the video. If you had the preset to be a certain size and there was tons of action in the video it may end up very pixilated and crappy looking. You could have a two action movie set to be 600 mb and it may be just horrible in picture quality. The CQ can figure out where it can compress and where it shouldn't so you end up a pretty good quality video. When it comes to CQ the lower the number the higher the quality.