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  1. How can i change the DAR from 16:9 TO 2:35:1 Using Megui??

    i am experimenting with encoding DVDs (Up-scaling TO 720P:- 1280*544) using x264

    the output is perfect but i want to change the DAR
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  2. 1280x544 is already 2.35:1 DAR if you don't specify otherwise. If you want to flag it anyway, set the SAR to 1:1. "--sar 1:1" on the x264 command line.
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  3. Originally Posted by jagabo View Post
    1280x544 is already 2.35:1 DAR if you don't specify otherwise. If you want to flag it anyway, set the SAR to 1:1. "--sar 1:1" on the x264 command line.
    u mean in the custom command line in megui MISC TAB

    and without the quotations??? or with??
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  4. I don't have a recent version of megui with the misc options. Just experiment with a short clip and see what works.
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  5. Unless you enable anamorphic encoding, MeGUI will always use a SAR (pixel aspect ratio) of 1:1, so a 1280x544 encode will display as 1280x544 (1280/544=2.359). Resizing without anamorphic encoding enabled always resizes to square pixels. MeGUI will add the correct SAR to the command line for you.

    Have a look in MeGUI's log file. It's reasonably informative. You'll see something like this (from an encode I'm running at the moment). The x264 info is mostly under the "standard error stream" section.

    [01/09/15 1:17:50 AM] resolution: 1276x690
    [01/09/15 1:17:50 AM] frame rate: 24000/1001
    [01/09/15 1:17:50 AM] aspect ratio: 638:345 (1.849)
    [01/09/15 1:17:50 AM] Job command line: "C:\Program Files\MeGUI\tools\x264\x264.exe" --level 4.1 --preset slow --tune film --crf 18.0 --keyint 240 --vbv-bufsize 78125 --vbv-maxrate 62500 --no-fast-pskip --stitchable --colormatrix bt709 --sar 1:1 --output "D:\Video.mkv" "D:\Video.avs"
    [01/09/15 1:17:50 AM] Process started
    [01/09/15 1:17:50 AM] Standard output stream
    [01/09/15 1:17:50 AM] Standard error stream
    [01/09/15 1:18:09 AM] avs [info]: 1276x690p 1:1 @ 24000/1001 fps (cfr)
    [01/09/15 1:18:09 AM] x264 [info]: using SAR=1/1
    [01/09/15 1:18:09 AM] x264 [info]: using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.1 Cache64
    [01/09/15 1:18:09 AM] x264 [info]: profile High, level 4.1
    For the record (I'm referring to using the AVS Script Creator) if you enable anamorphic encoding and switch to the script tab, you'll see the Display Aspect Ratio listed at the top (it'll change if you crop). When you save/load the script for encoding, MeGUI uses that DAR along with video resolution to set the appropriate SAR for the x264 encoder. Without anamorphic encoding enabled there's no DAR at the top of the script and the SAR will always be 1:1.

    Also for the record.... when you load a script into the video section and use the Preview button, the preview window shows the display aspect ratio down the bottom. You can actually change it, and if you do MeGUI will adjust the encoder SAR for you accordingly when you add the script to the queue for encoding. Changing it is probably not something you'd generally need to do though.
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  6. Originally Posted by hello_hello View Post
    Unless you enable anamorphic encoding, MeGUI will always use a SAR (pixel aspect ratio) of 1:1, so a 1280x544 encode will display as 1280x544 (1280/544=2.359).
    Does it actually specify the SAR or DAR in the h.264 stream or at the container level? Or does it just assume players will assume 1:1 SAR and play at 2.35:1 DAR? Of course, that's what all players do so it doesn't really matter. But I still like to specify 1:1 SAR in the h.264 stream because it's easy to change the flags if I ever want to. It's much harder to add SAR flags to an h.264 stream that doesn't have them.
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  7. Yes. MeGUI adds --sar 1:1 to the x264 command line (or an appropriate SAR for anamorphic encodes). Well.... the log files say it does and I checked several old ones. I never add --sar to the command line myself, and I leave it set to "default" in the x264 encoder configuration. All the x264 encoder settings in the command line from my earlier log file were set by me except for --keyint, which I leave to MeGUI to add based on the frame rate, and --sar.

    How do you modify the SAR in the h.264 stream? Not that it's something I need to do much but if I do I use the muxer/bitstream modifying build of ffmpeg, which is command line, so it's a pain anyway, but I'm pretty sure it sets the SAR whether or not the SAR flags already exist. Unless I'm remembering wrong. I haven't used it for a for while.
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  8. Originally Posted by hello_hello View Post
    How do you modify the SAR in the h.264 stream?
    I've used a program called H.264 Aspect Ratio Midifier. It has a GUI but can't add SAR flags, only change existing ones.
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