MP4 vs. MPEG4 vs. MPEG (H.264) vs. ?????

[goddi]

Hi Gary,

Increasing bitrate does the opposite of "degrade" a video. Within the considerations of the playing environment, increasing bitrate lends smoothness and presentation quality to a video and has nothing to do with compression. What it does have to do with is how much data is available to the processing environment within a given temporal period.

The purpose of the conversion within PTE is to make your video/slideshow play the best it "can" play in your PTE show. The only time lower bitrate is really needed is when you must spool the video through a bandwidth limited environment.

Keep in mind that "compression" is a convenience for primarily a couple of considerations. It give smaller file size for distribution and storage. When the video or image is played, it is "never" played in a compressed mode, but rather expanded in memory to its full original size. For example - when you take an 8 bit TIFF file and compress it with a jpg algorithm - let's say it started life as a 10 megapixel file and when compressed it becomes 800K in file size. As soon as it is loaded into your computer's memory, it expands to the original 10 megapixel size. The "only" differences are the load time and the file size for storage or transport across a bottleneck environment such as the internet. Likewise for video. Once it gets into the memory of the player or computer, it expands to the original pre-encoded size for playback.

Igor has carefully determined what works "best" in PTE and if the bitrate is increased from what you created with another product, it's because PTE can and will play it better with the increased bitrate.

Best regards,

Lin

==============================

Lin,

Thanks for the info on bitrate. I will not challenge it because I have zero understanding of how the bitrate of an original video can be increased. I know it is done but it is way above my head. But then I wonder why video cameras shoot at such a high bitrate and therefore take up so much space when they could just take the video at a very low bitrate and have a process to increase the bitrate afterwards with no 'degrade' of the video. Just wondering....

But, I can not accept the fact that if a 77mb original video is put through the PTE converter, and it comes out to be 336 mb, that this is a good thing. I would like better controls on the output. It is sort of like when I want to compress a jpg, I want to be able to have a choice as to how much compression.

Thanks... Gary

[Lin Evans]

Hi Gary,

Exceeding the "source" bitrate does not generally improve quality in any way, however if the bitrate is lower than the original it can often degrade quality. If the video came out of your camera at 77 mb file size with a particular bit rate, then exceeding that bitrate will not improve the quality, on the other hand, we have no easy way to know whether the increase in file size with a change in PTE "quality" is due "only" to the bitrate change or due to decompressing a file to make it easier on the system to play back smoothly. It takes "CPU and GPU horsepower" to decompress and play. It's much easier when the decompression is already done.

Don't "assume" that because the bitrate change is "correlated" with the file size that it is the primary culprit for the increase. It's much more likely that the compression level has also been altered and that it is much more responsible for file size increase.

Read this, it may help a bit...

http://www.lockergnome.com/media/2011/08/16/what-does-bit-rate-mean-in-video/

Best regards,

Lin

==============================

Lin,

Thanks for the info on bitrate. I will not challenge it because I have zero understanding of how the bitrate of an original video can be increased. I know it is done but it is way above my head. But then I wonder why video cameras shoot at such a high bitrate and therefore take up so much space when they could just take the video at a very low bitrate and have a process to increase the bitrate afterwards with no 'degrade' of the video. Just wondering....

But, I can not accept the fact that if a 77mb original video is put through the PTE converter, and it comes out to be 336 mb, that this is a good thing. I would like better controls on the output. It is sort of like when I want to compress a jpg, I want to be able to have a choice as to how much compression.

Thanks... Gary

[davegee]

I hope you can bend Igor's ear and take out the 'Quality' and put in 'Bitrate' as a control.

Thanks.... Gary

Gary is this what you mean:

DG

[goddi]

Gary is this what you mean:

DG

====================

Dave,

No. What I am referring to is the 'Quality' setting that you can adjust for the PTE conversion process, see attached. I have no idea what it is doing. I'd like to have a Bitrate slider to help reduce the file size, if needed. Nobody seems to think that size matters, but when people start putting in video clips, from my experience, the only way to do it (besides actually trimming off portions of the video) is to reduce the bitrate. Otherwise, we are going to have gigantic sized slideshows.

Gary

[Lin Evans]

Hi Gary,

It's sort of mixing peas and oranges here. The "Quality" slider is designed to let the casual user decide what they want in their conversion. The bitrate and "custom" capabilities are designed for the advanced user who understands the consequences of the changes.

Putting a "bitrate" control on the same page with the "Quality" slider would probably not make logical sense. If one had that capability, then it would countermand the very essence of what Igor was trying to accomplish with allowing one to change "Quality." Quality changes probably include bitrate, compression and other factors which the casual user could care less about. The emphasis here is on "Quality" of output. Igor considers 50% to be "normal" and that produces a reasonable file size with reasonable bitrate and reasonable compression. For the "ultimate" in quality, then the bitrate and compression must be adjusted properly for the individual video and that's where the various "algorithms" in Video Builder are implemented. Allowing us to "dink" with the settings of bitrate will very likely adversely affect the quality of output and how then are we to "trust" the relative numbers on the slider if we are messing with settings we don't really understand?

So if you really want to tinker with the output, use the custom features to manually modify your video rather than the Quality converter would be my take.

Best regards,

Lin

====================

Dave,

No. What I am referring to is the 'Quality' setting that you can adjust for the PTE conversion process, see attached. I have no idea what it is doing. I'd like to have a Bitrate slider to help reduce the file size, if needed. Nobody seems to think that size matters, but when people start putting in video clips, from my experience, the only way to do it (besides actually trimming off portions of the video) is to reduce the bitrate. Otherwise, we are going to have gigantic sized slideshows.

Gary

[goddi]

Hi Gary,

Exceeding the "source" bitrate does not generally improve quality in any way, however if the bitrate is lower than the original it can often degrade quality. If the video came out of your camera at 77 mb file size with a particular bit rate, then exceeding that bitrate will not improve the quality, on the other hand, we have no easy way to know whether the increase in file size with a change in PTE "quality" is due "only" to the bitrate change or due to decompressing a file to make it easier on the system to play back smoothly. It takes "CPU and GPU horsepower" to decompress and play. It's much easier when the decompression is already done.

Don't "assume" that because the bitrate change is "correlated" with the file size that it is the primary culprit for the increase. It's much more likely that the compression level has also been altered and that it is much more responsible for file size increase.

Read this, it may help a bit...

http://www.lockergno...-mean-in-video/

Best regards,

Lin

============================

Lin,

Thanks for the link. It helps me see that I am not the only one that thinks this is a 'black box'. There are a lot of factors working here that we can't nail down. But...it still leaves me with the question why PTE increased the size of the 77mb file so dramatically to 336mb during its conversion process. As you and the video link said, exceeding the 'source' bitrate does not generally improve quality. But I have found that reducing it without going too far retains quality and reduces the file size. Since there is no way to take into account all the other 'things' that are involved, I can only work with what I know and can control and that is the bitrate. All I am saying is, to me, the video's file size is important and the only control I seem to have in addition to trimming it, is to reduce the bitrate. I'd like PTE to have that functional choice in the conversion process. We would be able to fiddle with the bitrate until be see any reduction in quality, and let the 'CPU and GPU' do whatever it needs to do, because that we can't immediately factor in or tinker with.

Gary

[goddi]

Hi Gary,

It's sort of mixing peas and oranges here. The "Quality" slider is designed to let the casual user decide what they want in their conversion. The bitrate and "custom" capabilities are designed for the advanced user who understands the consequences of the changes.

Putting a "bitrate" control on the same page with the "Quality" slider would probably not make logical sense. If one had that capability, then it would countermand the very essence of what Igor was trying to accomplish with allowing one to change "Quality." Quality changes probably include bitrate, compression and other factors which the casual user could care less about. The emphasis here is on "Quality" of output. Igor considers 50% to be "normal" and that produces a reasonable file size with reasonable bitrate and reasonable compression. For the "ultimate" in quality, then the bitrate and compression must be adjusted properly for the individual video and that's where the various "algorithms" in Video Builder are implemented. Allowing us to "dink" with the settings of bitrate will very likely adversely affect the quality of output and how then are we to "trust" the relative numbers on the slider if we are messing with settings we don't really understand?

So if you really want to tinker with the output, use the custom features to manually modify your video rather than the Quality converter would be my take.

Best regards,

Lin

==============================

Lin,

I think we've beat this horse to death already.

For me, the 'Quality' slider means nothing. Why not have a 'Advance' button to bring in any advanced features? At least with bitrate, you know what you have done and can learn what a good number is for your purposes and you are dealing with a known video factor. If you think setting the bitrate is 'dinking', that is what I feel when I am using the 'Quality' slider. I have not idea what it is doing. If setting the bitrate too low adversely affects the quality, at least you know why and you can gradually increase the bitrate with a better understanding of what is going on. You said to use the 'custom features' to manually modify the video. Where are these 'custom' features in the PTE conversion window? All I see is the 'Quality' slider.

If PTE users are not concerned with the ultimate file size when they are inserting video, then you are right to stick with the 'Quality' slider. But...I think we need something to help bring down the file size and the only function that is easily available and eventually understandable is being able to adjust the bitrate. Just my 2 cents. I am pretty much in the dark about all this but I figured out what the affects are when adjusting the bitrate.

Gary

[goddi]

Hi Gary,

It's sort of mixing peas and oranges here. The "Quality" slider is designed to let the casual user decide what they want in their conversion. The bitrate and "custom" capabilities are designed for the advanced user who understands the consequences of the changes.....

Best regards,

Lin

=====================

Greetings All,

After poking around the Freemake site for a while, I just came across a page on their site that is entitled, "Reducing Video: When Size Does Matter:"

http://www.freemake....ze-does-matter/

For those interested in taking more control over reducing the size of their video files, it is interesting. It makes the point about reducing the bitrate and using the H.264 video codec, things we have been kicking around in this post. Food for thought.

Gary