![]() ![]() (use the Distort option or overlay tracks to resize the frame) May be a problem as your original is using widescreen 16:9 (1280 x 720)ġ / the frame will be distorted – people will look quite tall and thin.Ģ / the left and right border can be cropped to create the 4:3 shape, you will lose that detail. I chose Frame Based as your original Mpeg4 will probably be using that and not interlaced. The data rate of 8000 allows for 60ish minutes at 4Gb file size, this is high DVD quality, at 4000kbps is equivalent to VSH quality (2 Gb) You do not give full details of your video file, right click in the timeline and select properties, what are they? I assume you will be using 25fps, your Mpeg 4 could however be using 30fps? You are limited in using the industries standard properties for DVD Using Settings Make Movie Templates Manager create a new Mpeg2 Template But the file size would be much larger than the original and the quality possibly less than the original. I can't say with any exactitude, but converting your original mpeg-4 to high def Blu-Ray compatible mpeg-2 would probably require roughly double, and probably higher, the original bitrate to maintain roughly a similar level quality. You would probably also be moving from 1280 x 720 to 1920 x 1080 (0r perhaps 1440 x 1080) which will require in effect the invention of new pixels which is usually done by simply duplicating existing pixels (and thus producing further quality loss). But again, you would be converting a highly compressed format to a format using less compression, and thus producing larger files - and depending on the bitrate used (and bitrate determines quality), the end file would be very much larger that DVD-quality mpeg-2. ![]() The matter becomes even more complicated if, instead of DVD quality mpeg-2, you are talking about converting the mpeg-4 to high def mpeg-2 which in effect is Blu-Ray (leaving aside the question of HDV mpeg-2 though similar arguments apply). One hour of such video would be around 4.3 GB. But converting that to standard def mpeg-2 using that bitrate I mentioned above (8000 kbps) means you will never be able to maintain the same size in the end video, even if the quality remains fairly high. Your original mpeg-4 has a bitrate of 4442 kbps - which I have to say is relatively low for high def video. And the highest quality you can achieve with that format is from a bitrate of around 8000 kbps. If it is a DVD, then that is standard definition mpeg-2, which will have a smaller frame size (720 x 576 PAL or 720 x 480 NTSC) which will notionally be of lesser quality than the original. or is it? You haven't in fact told us what you are wanting to make with the converted video. On top of that, you are going from high definition mpeg-2 (which is what 1280 x 720 video is) to what I am presuming is meant to be standard definition mpeg-2. So to compensate, you need to use as high a bitrate as is consistent with mpeg-2. And again you have to think of the loss of quality caused by the conversion in its own right. But converting it to mpeg-2 means you are lowering the compression, so the resulting file will be bigger. That's how they get a smaller file, though with the algorithms used, the quality remains high. Next, mpeg-4 is much more highly compressed than mpeg-2. In other words, every time you render it (and that includes conversion), it will lose some quality. First off, mpeg - be it mpeg-4 or mpeg-2 - is a lossy format. ![]() The question of quality and size are in fact the key, but not in the sense you might think. What data rate should I put using custom then mpg files to keep same quality and size If I convert it using the simple way in vs pro 圆 through dvd then mpeg2 it will convert it with higher size and higher bitrate ![]()
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