Blazing Saddles Done With A Constant Bitrate?

[ZenMystic]

Recently I bought Blazing Saddles on DVD. I had also previously bought a download version for my ps3/psp. I have been thinking more and more about encoding my own dvd's I have bought instead of rebuying them again for my psp.

I thought I would try with Blazing Saddles so I could compare with the version I bought with the one I made.

The file info I get from the file I bought for my psp is this:

Rez:720x480
video avc 2000 kbps
audio aac 256 kbps
sampling 48.000 khz

99% of the files I have bought gave this same info. Only a very few so far show different rate for video or audio.


But on the file I encoded I get this:

Rez: 720x480
Video avc - kbps why? Is it because the bitrate is changing and not constant like in the bought version?

Audio aac 255 kbps Again why? before I mux the audio with video it is 256 as it should be. But after mux it changes to 255 why?

I am very new to x264.

[thewebchat]

Why do you want constant bitrate? The 256 vs 255 is probably a result of rounding errors.

[ZenMystic]

Because that is how the ones I have bought turn out. So I would like mine to be the same. I would also just like the "know how"

Can anyone help me?

[foxyshadis]

I have no idea how you get the file info, but MediaInfo is a better tool for obtaining it.

You can encode to 2000 kbps just by plugging that number into your encoder, on two-pass or one-pass-bitrate modes. It's not constant throughout each, and I guarantee the originals aren't (I've seen several of them), that's just the average. I believe they have a single one-click processing application that they use for every movie that they release, that's why everything's the same.

As for why the bitrate change, that's one of the bizarre little quirks of muxers: The audio container (the raw AAC) has some overhead that's stripped out and replaced by the muxer's overhead. For some formats it's more, for some it's less. Such a tiny amount isn't worth worrying about, if you absolutely must, raise the audio bitrate slightly.

[prOnorama]

Why? Contant bitrate is not very efficient. Some movies need more bitrate than others, it all depends on the quality of the source, type of movie etc.

With variable bitrate you can save space if the bitrate of 2000 Kbps is not needed for a movie. Also the bits get distributed across the movie so the parts that need more bitrate get more bitrate, improving quality.

Try RipBot264 it's an easy to use program for x264 video conversion

[ZenMystic]

I get the info about the file from the psp itself when I put it on there. But the movies I encode and put on the always say:

"Video - KBPS."

But bought ones always say something like:

"Video AVC 2000 KBPS" or something like that. How do I get my encoded files to act the same way?


I tried RipBot264 but it will only rip the audio to mono and not stereo and will not allow me to change it.

[ZenMystic]

When I encode a video file to play on my psp the resolution seems to determine the aspect ratio. Yet I know with movies I have bought online that the resolution is 720x480 and it plays in wide screen on both my psp and ps3. How do I get videos that I encode to behave the same way?

The only way thus far I have been able to play wide screen on the video file I encoded is to have a different resolution.

am at my wits end here trying to figure this out....

The only thing I can think of it that the videos I buy online are done on one aspect ratio and the resulting mp4 file is then altered a flag or something inside the file to make the psp "think it is wide screen and play it thus. But this is just a wide guess on my part.

Can anyone out there shed any light on this?

How do I play video files at 720x480 and it be in wide screen (black bars at top and bottom if needed.) And not from left to right, which turn it into 4:3 which the psp is doing with my video files I have made.

[thewebchat]

The aspect ratio can be signaled as a SAR flag in the AVC headers or it can be specified in the video container (AVI, MP4, MKV, etc). Look at the "sar" parameter to x264. It sets the appropriate flag in the video headers that a compliant player will use to display the video in the correct aspect ratio.

If you don't know how to set the SAR correctly, look at this table of common values on Wikipedia: http://en.wikipedia.org/wiki/Pixel_aspect_ratio#Pixel_aspect_ratios_of_common_video_formats

[ZenMystic]

The problem was solved using yamb to signal 16:9 flag for the .mp4 container.

Thanks for the help guys...

[ZenMystic]

I would very much like my encodes to give a bit rate just like my bought ones do.

Question #1 How do I write this info to the mp4 container on video files I encode????
if that is were the info would even go??


Question #2 Is there a way I can embed my thumbnails into my video files? So I do not need a separate image file in another folder.