Who has the new AV Composite cable and 1.1.3?

Discussion in 'iPod touch Accessories' started by TheSpaz, Jan 26, 2008.

  1. TheSpaz macrumors 604

    TheSpaz

    Joined:
    Jun 20, 2005
    #1
    I'm hoping that I can find more people with this problem. I have the $50 Apple AV Composite cable that plugs into the Dock connector for use with the iPod touch. I've recently upgraded to 1.1.3 and now when I watch videos on my TV using the AV cable, it stutters every 15 seconds or so... it's like a small skip in the framerate. I'm trying to find other people who have the same setup. AV Composite cable + Firmware 1.1.3. If you have this setup, can you please test it for me and see if yours skips too? I've restored 3 times already.

    Just to point out, I downgraded to 1.1.2 and the problem went away... I had silky smooth video without and problems, so I upgraded back to 1.1.3 and the stuttering came back.
     
  2. darkblu macrumors regular

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    Jan 20, 2008
    #2
    i have the new component AV cable and i can confirm similar behavior under 1.1.3. basically, it shows as occasional stuttering for the duration of one or two frames. and in my case it does not happen periodically, but rather shortly after a major transitional frame (i.e. when the scene changes) - within several seconds after that, as if the video lost sync and the playback had to compensate by frame skipping.

    it's not that annoying (you have to look for it in most of the cases to notice it) but nevertheless i hope they fix that in the next firmware release.
     
  3. TheSpaz thread starter macrumors 604

    TheSpaz

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    #3
    Anyone else care to step up and let me know if it works for you?
     
  4. OrangeCuse44 macrumors 65816

    OrangeCuse44

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    Oct 25, 2006
    Location:
    Long Island, NY
    #4
    I have yet to upgrade, but hasnt the stuttering video playback been an overall problem with 1.1.3 even on the touch itself?

    Btw, how is the quality of video on your television using the dock connected cable? Are you using default handbrake iPhone settings?
     
  5. TheSpaz thread starter macrumors 604

    TheSpaz

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    #5
    I haven't been using the iPhone settings in Handbrake. I like to use the AppleTV settings since it is still compatible with the iPhone/iPod touch yet it's near-DVD quality and full DVD resolution. I don't see the skipping unless I've got it plugged into the TV, so I think it's just the video-out capabilities of 1.1.3 that is screwed up.
     
  6. darkblu macrumors regular

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    #6
    compression quality aside, the ipod's maximal video resolution is 640x480, whereas a widescreen dvd is 704/720 x480, and that resolution difference is noticeable on a widescreen TV.

    ditto. skipping occurs only at the TV, which may have something to do with the increased target framebuffer (640x480 vs 480x320) and an underperforming codec in 1.1.3.
     
  7. TheSpaz thread starter macrumors 604

    TheSpaz

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    #7
    The resolution can be full anamorphic DVD resolution... In fact, that's what the iTunes rentals are. I have ripped full quality DVDs that are over 720px wide... I think you just can't go OVER 480px high.
     
  8. darkblu macrumors regular

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    Jan 20, 2008
    #8
    interesting. so you're saying that you've been able to playback > 640-column-wide video material on the ipod? that'd be a very nice undocumented feature.
     
  9. TheSpaz thread starter macrumors 604

    TheSpaz

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    Jun 20, 2005
    #9
    It's not undocumented. 480p means that it can be up to 480px TALL (That's what 480p means). So it can be 480px tall and as wide as it needs. I've run video over 800px wide.
     
  10. MacinJosh macrumors 6502a

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    Finland
    #10
    You're saying iTunes rentals are anamorphic? What's their native resolution?

    Full quality widescreen DVD (NTSC) is 720x480 when it's not strecthed. When stretched, since it's anamorphic and requires it to display in the correct aspect ratio, the resolution essentially becomes 852x480. Essentially, because it occupies that amount of pixels when stretched on an LCD display even though it's 720x480. Same applies for for PAL (european) DVDs except their resolutions are 720x576 native an 1024x576 stretched.

    This only applies to widescreen movies which all new releases have been in the past several years.

    Joshua.
     
  11. TheSpaz thread starter macrumors 604

    TheSpaz

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    #11
    iTunes rentals are anamorphic. I checked and the width was over 800px wide. I forget exactly how wide it was because I have since erased it but, it was 800-and-something pixels wide and it played on my iPod touch. It was NOT 720px wide.
     
  12. darkblu macrumors regular

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    Jan 20, 2008
    #12
    then that'd be quite intresting, considering the device's specs:
    http://www.apple.com/ipodtouch/specs.html

    thank you, but i know all that. i was referring to the source resolution, in the context of the device's specs (see link above).

    appleTV widescreen 'DVD quality' is 848x480, IIRC. which technically would not pass as anamorphic, as the stretch is minimal (those few columns off the sides can easily go toward overscan). anamorphic is when there's a non-uniform (aka -isomorphic) stretching of the source material to the target aspect ratio (as in 720 -> 854, @480 rows). so appleTV's DVD rentals would qualify as 'EDTV-res widescreen isomorphic', if we are to be technically correct ; )
     
  13. TheSpaz thread starter macrumors 604

    TheSpaz

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    #13
    All I'm really trying to say is that the iPod touch supports 480p meaning that it cannot go over 480 pixels tall but, the width doesn't matter. I've tested it. It really does work. This is where I found out the supported resolution of the iPod touch/iPhone http://store.apple.com/1-800-MY-APP.../ipod_accessories/cables_docks&nplm=MB128LL/A -- I knew I saw it somewhere.
     
  14. MacinJosh macrumors 6502a

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    #14
    Probably not with H.264 or...?
     
  15. darkblu macrumors regular

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    Jan 20, 2008
    #15
    i see now. that page describes the analog-signal capabilities of the compatible ipods as per the NTSC and PAL standards, but it does not say anything about the video-source decoding capabilities of each of the devices (not that there are any differences across the different ipods). for instance, a progressive NTSC signal is always 480 picture-rows tall (i.e. it has more rows but only 480 of them carry picture information), ergo that '480p' moniker. but that does not mean the soure material has 480 rows - that could be 16x16, and the ipod will still produce '480p' output signal.

    what i was looking for, OTOH, was the limitation of the device to decode video streams up to a given res. now that is given as '640x480' in the device specifications, but your experience speaks otherwise, which is interesting as it appears to be undocumented. so thumb up for that bit of info.
     
  16. TheSpaz thread starter macrumors 604

    TheSpaz

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    #16
    I almost couldn't follow any of that, but you're welcome.
     
  17. TheSpaz thread starter macrumors 604

    TheSpaz

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    Jun 20, 2005
    #17
    Just rent an iTunes movie and throw it on your iPod or better yet, rip your own DVD with Handbrake with the anamorphic setting on and see for yourself that it does work. I was surprised too when I tried this out. I heard that the iPod touch has a 400MHz processor in it.
     
  18. darkblu macrumors regular

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    Jan 20, 2008
    #18
    AAMOF, with this info now i plan to re-rip all my DVD collection to anamorphic ; )

    update: no luck with handbrake, and the problem seems to be rooted in the x264 encoder - whenever i use an h264 ipod profile, the encodings end up as 640 columns max, no matter what handbrake *thinks* it's producing. at least the encodings are anamorphic as requested, but i have not yet tried how they play back on the 'pod. i'll post an update tonight when i get back to the issue.

    update: nope, no luck with the anamorphic material produced by handbrake either - the 'pod plays it at a wrong aspect ratio. frankly, i'm running out of test options here, as x264 clearly won't encode more than 640 columns for the 'pod (not under handbrake anyway), and i don't have another encoder that can produce h264 video good for the ipod.
     
  19. TheSpaz thread starter macrumors 604

    TheSpaz

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    #19
    Well, I've updated to 1.1.4 and the problem still persists. No love for me I guess.
     
  20. TheSpaz thread starter macrumors 604

    TheSpaz

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    #20

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