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  1. hey i got a problem. some of my videos work fine but some of the videos give me trouble. ive been converting my music video selection to mpeg-4 with videora ipod converter using a variety of resolutions but many of my videos don't play on my ipod although they play fine in quicktime. i transfer them fine using itunes, but when i select the video on my ipod it goes to a black screen, waits about 15 seconds and then goes back to the menu. the files so far that don't work are using these resolutions (not sure if the resolution is the problem).
    538x426
    540x426
    548x420
    552x416
    634x362
    552x416
    552x416
    546x420
    544x422
    546x420


    All of these are using 768 kbps video and 128 kbps audio and are cropped by various amounts. I tried lowering the video to 640 kbps but it didn't help.

    any suggestions?
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  2. Member
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    are you encoding in mp4 or h.264?

    your safest bet is to encode at 320x240 mp4 with a bitrate of 768 for video and 160 for audio.

    while you can go up to higher resolutions, if you don't intend on playing back mainly on TVs, it will only decrease the video quality (more resolution with a low bitrate = pixelation/macroblocking). the LCD on an ipod only displays 320x240, everything else is scaled to this.
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  3. Member
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    Some rules for encoding:

    Multiples of 16 for both width and height - 368x208, 400x176, etc. If the math doesn't work out perfectly (considering the source's dimensions), use whatever is closest but stick with the "rule of 16's".

    For H264 you have 76,800 pixels. While some may indicate that anything above 320 width reduces the quality, that has not been my experience (and I have transcoded hundreds of files since I bought my 5G iPod last year). The 76,800 pixel limit is your friend; get as close to it as you can but, in NO case exceed the limit. (This paragraph applies to video you intend to display on your TV with the AV cable; 320 x whatever is mathematically proper is fine for display on the iPod screen - but you still must adhere to the "rule of 16's".)

    Audio - 48K (not 41K), 192kb may be overkill unless the audio in the source is something really special. I use 128kb or 160kb normally. YMMV.

    Bitrate - I use ffmpegX and, at any of the allowable sizes for H264, I set the bitrate to about 20% above recommended. This usually is around 300-325kb. Extremely high bitrates will cause the issue you describe (shutting off in 15 seconds).

    Let us know if this helps.
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  4. Member
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    Originally Posted by rumplestiltskin
    Audio - 48K (not 41K), 192kb may be overkill unless the audio in the source is something really special. I use 128kb or 160kb normally. YMMV.
    just in case of confusion...
    the ipod with video support can only use up to 160kbps 48khz AAC audio.
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  5. Member
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    Originally Posted by choirislife923
    just in case of confusion...
    the ipod with video support can only use up to 160kbps 48khz AAC audio.
    Yes, quite right; my bad.
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