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  1. I'm trying to get some videos to work on my phone. My phone plays wmv, 3gp, and mp4 (but doesn't support H.264). I was able to find some videos that are mp4's with H.264 encoding and that are amazing quality for being 35MB and 22 minutes long (tv show). However, when I try to convert them to a format that my phone supports, I lose a lot of quality. I've even tried converting them to H.246 mp4's with the exact same bitrates and everything (to duplicate the files) and I lose lots of quality.

    So what is it about their encoding that makes the quality impossible to maintain in conversion? As far as I can tell, I'm outputing files with the same statistics as the input files.

    The original files are 320x240, 112kbps video, 95 kbps stero 48kHz, 23 fps, ~22 mins, mp4 with h.264 encoding.

    I'm using Free Video Converter from Koyotesoft.

    If anybody can explain to me what's going on and/or how I can get these videos on my phone while maintain their quality and size of ~35MB, let me know. Thanks.
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  2. I'm a MEGA Super Moderator Baldrick's Avatar
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    Try something else, like handbrake.

    Anything with FREE in the name is usually crap.
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  3. Ok, I've played around with Handbrake a bit. I seem to be getting some better results, especially with the h.264 codec. However, my phone doesn't support that and I'm still having trouble getting decent quality using the mpeg4 codec and keeping the file size <40MB. Motion in the video causes blurriness and blockiness. What I have working now is passable, but I'm curious to know if there are any other techniques or options that will help me maintain more quality with this codec.
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  4. Member hech54's Avatar
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    The problem is you are using video that have already been compressed....and compressing them more/again.
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  5. Are you sure? Because I can convert it with the h.264 codec and the quality is significantly higher.
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  6. Member Cornucopia's Avatar
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    I've said this before, but I'll say it again:

    Think of it this way...
    You ORIGINAL SOURCE material was 100% quality. Your original h.264 copies are, say, 60% of that quality. That's .6 x 100.
    Even though you are decompressing this, you don't GAIN BACK any of the original quality.
    So when you recompress, your NEW master is at 60%. Even if you were to recompress at the same bitrate and using the same codec (h.264) and could make use of the statistical similarities in the pre-compressed file, you might at best NOW get, say 80%. So, .8 x 60 = 48% quality.
    If you used a different codec (like WMV or MP4) and a lower bitrate, your efficiency might drop to 50%. So then, .5 x 60 = 30%.

    You can't squeeze blood out of a stone/turnip, nor MORE water out of an already dry sponge.

    That's why you DON'T want to recompress compressed material.

    Scott
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  7. Member hech54's Avatar
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    Exactly. Video and audio compressions are NOT like ZIP files. Once it is compressed it can NEVER be put back to original or even close to original. Once the damage is done....it's done.
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  8. I'm a MEGA Super Moderator Baldrick's Avatar
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    Yep, find a better source and you will get better quality.
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