@KenWicks, @Scenestealer

Hi

As Scenestealer says there is definitely something wrong with the export settings - this is my MainConcept MPEG export default

However the MediaInfo data for the average bitrate is correct - these are the results for a black image export using the default settings above.

Format settings, GOP                     : M=3, N=12
Format settings, picture structure       : Frame
Duration                                 : 59 s 920 ms
Bit rate mode                            : Variable
Bit rate                                 : 233 kb/s
Maximum bit rate                         : 9 500 kb/s
Width                                    : 720 pixels
Height                                   : 576 pixels
Display aspect ratio                     : 16:9
Frame rate                               : 25.000 FPS
Standard                                 : PAL
Color space                              : YUV
Chroma subsampling                       : 4:2:0
Bit depth                                : 8 bits
Scan type                                : Interlaced
Scan order                               : Bottom Field First

While there is something wrong with the MC export settings, the very low average bitrate reported for the 'black video' is correct - there is nothing in the video that changes or has detail that requires a higher bitrate so the encoder opts for the minimum possible.

Once the default settings are fixed, try exporting with the real video and then look at the MediaInfo.

. . . . despite there being very little motion in the video . . . .

Depending on how little the motion is it is possible you will get a lower bitrate then the export settings specify.

Please read this topic and put your computer spec and MEP full name and version in your signature for future reference.

HTH

John EB

@KenWicks, @Scenestealer

Hi

As Scenestealer says there is definitely something wrong with the export settings - this is my MainConcept MPEG export default

However the MediaInfo data for the average bitrate is correct - these are the results for a black image export using the default settings above.

Format settings, GOP                     : M=3, N=12
Format settings, picture structure       : Frame
Duration                                 : 59 s 920 ms
Bit rate mode                            : Variable
Bit rate                                 : 233 kb/s
Maximum bit rate                         : 9 500 kb/s
Width                                    : 720 pixels
Height                                   : 576 pixels
Display aspect ratio                     : 16:9
Frame rate                               : 25.000 FPS
Standard                                 : PAL
Color space                              : YUV
Chroma subsampling                       : 4:2:0
Bit depth                                : 8 bits
Scan type                                : Interlaced
Scan order                               : Bottom Field First

 

While there is something wrong with the MC export settings, the very low average bitrate reported for the 'black video' is correct - there is nothing in the video that changes or has detail that requires a higher bitrate so the encoder opts for the minimum possible.

Once the default settings are fixed, try exporting with the real video and then look at the MediaInfo.

. . . . despite there being very little motion in the video . . . .

Depending on how little the motion is it is possible you will get a lower bitrate then the export settings specify.

Please read this topic and put your computer spec and MEP full name and version in your signature for future reference.

HTH

John EB

 

Hi there, thanks so much for your help on this so far.

What I’m still confused about is why both Mediainfo and Windows say that the data rate/maximum bitrate is the exact value that is set as the maximum bitrate in the encoder. Doesn’t the maximum bitrate of a video mean the overall bitrate? If it doesn’t then why does Windows only tell you the data rate, which is the same as maximum bitrate in Mediainfo?

@KenWicks

Hi

. . . . Doesn’t the maximum bitrate of a video mean the overall bitrate? . . .

Sometimes definitions are confusing:

Overall bitrate is the average bitrate of the video ie Bit Rate in MediaInfo, however the bitrate can vary within the video from moment to moment depending on how much data is required to maintain quality ie in statics or low detail scenes less data is required compared to a scene with a lot of detail or movement.

However the encoder should be limited to a Maximum bitrate by the Max bitrate setting, which can, if it is too low, lead to loss of perceived quality eg: blockiness or a solarized effect.

. . . . .why both Mediainfo and Windows say that the data rate/maximum bitrate is the exact value that is set as the maximum bitrate in the encoder . . . .

That is correct and what should be reported - AFAIK the Maximum bitrate is included in the file header data so that the decoder can check whether the video is playable ie that it is not suddenly hit with a bitrate that is higher than its capabilities which can cause a crash.

As has been said before the preset needs fixing, the values shown in your images above are unrealistic and possibly impossible for the encoder - in the case of the 2 images you posted you will see that the actual bitrate is higher (408 kb/s) than the maximum settings, this is puzzling as to why this has happened - it looks like the encoder has overridden the maximum rate setting.

HTH

John EB

@KenWicks

In the case of the 2 images you posted you will see that the actual bitrate is higher (408 kb/s) than the maximum settings, this is puzzling as to why this has happened - it looks like the encoder has overridden the maximum rate setting.

HTH

John EB

 

Yes, this is the main point that I’m trying to make. Why is it that the bitrate of my videos are ending up larger than what I set as the maximum bitrate??

Also, are you telling me that “maximum bitrate”, in Mediainfo, is not the actual bitrate of the whole video? If this is the case then, as I mentioned before, why does Windows only tell you what the maximum bitrate is? I was under the assumption that the data rate was in fact the actual bitrate of the video.

@KenWicks

I really think it would help if we could discuss your points based on an example with less extreme (small) BR settings and only 2kbps difference set between the average and maximum. As I said, I would be surprised if the encoder could make any sense of such small amounts. Did you try resetting the Standard template to defaults?

@KenWicks

Hi

. . . . Why is it that the bitrate of my videos are ending up larger than what I set as the maximum bitrate . . . .

The settings you set above are not realistic for the resolution of video and the encoder is overriding the maximum rate setting, it is not possible to create the video with those settings and resolution and preserve the quality.

This is what it will look like with the lowest settings I can export with ie

Bit rate mode                            : Variable
Bit rate                                 : 1 032 kb/s
Maximum bit rate                         : 1 000 kb/s
Width                                    : 720 pixels
Height                                   : 576 pixels
Display aspect ratio                     : 16:9
Frame rate                               : 25.000 FPS

As you can see the bit rate is just over 5 x higher then your settings and the quality is very poor.

It also raises the question why are you setting the bitrates so low?

. . . . are you telling me that “maximum bitrate”, in Mediainfo, is not the actual bitrate of the whole video . . . .

As I said above Overall bitrate is the average bitrate of the video ie Bit Rate in MediaInfo . . . . the encoder should be limited to a Maximum bitrate by the Max bitrate setting

Actual bitrate is a misnomer because the bitrate is not fixed in the export setting you posted so it can vary throughout the length of the video.

HTH

John EB

@KenWicks

I really think it would help if we could discuss your points based on an example with less extreme (small) BR settings and only 2kbps difference set between the average and maximum. As I said, I would be surprised if the encoder could make any sense of such small amounts. Did you try resetting the Standard template to defaults?

Yes, but exactly the same thing happened. For some reason the encoder seems to be ignoring the set maximum bitrate and is going above that.

@KenWicks

Hi

. . . . Why is it that the bitrate of my videos are ending up larger than what I set as the maximum bitrate . . . .

The settings you set above are not realistic for the resolution of video and the encoder is overriding the maximum rate setting, it is not possible to create the video with those settings and resolution and preserve the quality.

This is what it will look like with the lowest settings I can export with ie

Bit rate mode                            : Variable
Bit rate                                 : 1 032 kb/s
Maximum bit rate                         : 1 000 kb/s
Width                                    : 720 pixels
Height                                   : 576 pixels
Display aspect ratio                     : 16:9
Frame rate                               : 25.000 FPS

As you can see the bit rate is just over 5 x higher then your settings and the quality is very poor.

 

It also raises the question why are you setting the bitrates so low?

 

. . . . are you telling me that “maximum bitrate”, in Mediainfo, is not the actual bitrate of the whole video . . . .

As I said above Overall bitrate is the average bitrate of the video ie Bit Rate in MediaInfo . . . . the encoder should be limited to a Maximum bitrate by the Max bitrate setting

Actual bitrate is a misnomer because the bitrate is not fixed in the export setting you posted so it can vary throughout the length of the video.

HTH

John EB

 

 

So what is the meaning of maximum bitrate in Mediainfo if “Bitrate” is the average bitrate? And also, in that screenshot you posted, how can the bitrate (1,032kbps) be more than the maximum? (1,000kbps) that’s what I’ve been trying to understand, how it is that the average bitrate of a video can be more than the max that was set in the encoder settings.

@KenWicks

Hi

. . . . what is the meaning of maximum bitrate in Mediainfo if “Bitrate” is the average bitrate? . . . .

I have already clearly stated what the difference is above.

. . . . how can the bitrate (1,032kbps) be more than the maximum? (1,000kbps) that’s what I’ve been trying to understand, how it is that the average bitrate of a video can be more than the max that was set in the encoder settings. . . .

As I have already said the settings you used are not realistic for the resolution of video, just as my settings were not realistic for the video clip I used in the example above.

I ask again - why are you setting the bitrates so low?

John EB

@KenWicks

Hi

. . . . what is the meaning of maximum bitrate in Mediainfo if “Bitrate” is the average bitrate? . . . .

I have already clearly stated what the difference is above.

. . . . how can the bitrate (1,032kbps) be more than the maximum? (1,000kbps) that’s what I’ve been trying to understand, how it is that the average bitrate of a video can be more than the max that was set in the encoder settings. . . .

As I have already said the settings you used are not realistic for the resolution of video, just as my settings were not realistic for the video clip I used in the example above.

I ask again - why are you setting the bitrates so low?

John EB

 

I just used those values as a random example.

So let me get this clear in my head...in Mediainfo, the overall/average video bitrate is where it says “Bitrate”?

Also, when you right-click on a file in properties then details in Windows, why doesn’t that also tell you the bitrate?

@KenWicks

Hi

. . . . . Mediainfo, the overall/average video bitrate is where it says “Bitrate” . . . .

Correct.

. . . . when you right-click on a file in properties then details in Windows, why doesn’t that also tell you the bitrate . . . .

It does, however it give different results and is a little confusing as you can see below

Data rate = Bit rate in MediaInfo, however it gives a different value for the video compared to MediaInfo:

19107 kbps = 18.65 Mb/s

Total bitrate is the sum of the video Data rate and Audio Bit rate - and should not be in the Video section

For the same clip MediaInfo says:

Video

Bit rate mode                       : Variable
Bit rate                                 : 18.3 Mb/s

Audio

Bit rate                                 : 384 kb/s
Channel(s)                           : 2 channels

For the purposes of posting a video analysis in the forum we use MediaInfo - it gives us more detail about the video and audio.

If you just want a rough guide on what the video and audio rates are, Windows (File) Explorer is close enough.

HTH

John EB

@KenWicks

Hi

. . . . . Mediainfo, the overall/average video bitrate is where it says “Bitrate” . . . .

Correct.

. . . . when you right-click on a file in properties then details in Windows, why doesn’t that also tell you the bitrate . . . .

It does, however it give different results and is a little confusing as you can see below

Data rate = Bit rate in MediaInfo, however it gives a different value for the video compared to MediaInfo:

19107 kbps = 18.65 Mb/s

Total bitrate is the sum of the video Data rate and Audio Bit rate - and should not be in the Video section

For the same clip MediaInfo says:

Video

Bit rate mode                       : Variable
Bit rate                                 : 18.3 Mb/s

Audio

Bit rate                                 : 384 kb/s
Channel(s)                           : 2 channels

For the purposes of posting a video analysis in the forum we use MediaInfo - it gives us more detail about the video and audio.

If you just want a rough guide on what the video and audio rates are, Windows (File) Explorer is close enough.

HTH

John EB

Ah, that makes a lot more sense to me now, thank you. However, I notice also that the data rate value in Windows is exactly the same value for maximum bitrate in Mediainfo. That’s why I thought that data rate in Windows is telling you the maximum bitrate of the whole video, and that maximum bitrate in Mediainfo (same value) is also telling you the same. So it’s a bit confusing why maximum bitrate in Mediainfo is actually not the maximum, overall bitrate.

@KenWicks

. . . . . I notice also that the data rate value in Windows is exactly the same value for maximum bitrate in Mediainfo . . . .

In the case of my example - this is not true - Explorer 19.03 Mb/s vs MediaInfo 24.0 Mb/s (I set this in the export dialog).

. . . . it’s a bit confusing why maximum bitrate in Mediainfo is actually not the maximum, overall bitrate . . . .

Do you mean the real maximum bitrate that is in the video, if so this would be called the Peak bitrate see image below - this is the mp4 version (for the Internet) of the one I used in my example above.

As you can see above, the bitrate changes greatly throughout the duration of the video.

In this example - I could not use the previous m2ts file because the software used is old and does not support newer formats - the lowest bitrate is 2756 kbps and the peak 20923 kbps (pink graph), ie the peak rate is 7.6 x higher than the lowest (pink graph).

The Average bitrate (blue graph) is a true average and agrees with MediaInfo.

The encoder also over-rode the Maximum Bitrate setting I set (18000 kbps) many times because the detail in the source video and images was extremely fine as shown in the example below.

The Bitrate viewer is a useful tool, however I use it very rarely.

To round off this comment, the one tip that is frequently given is not to modify the export presets in MEP. They are already optimised for the various video formats and resolutions.

Changing these settings can result in actually making the video visually worse and also end up wasting a lot of time for very little, if any, gain.

HTH

John EB

@KenWicks

. . . . . I notice also that the data rate value in Windows is exactly the same value for maximum bitrate in Mediainfo . . . .

In the case of my example - this is not true - Explorer 19.03 Mb/s vs MediaInfo 24.0 Mb/s (I set this in the export dialog).

. . . . it’s a bit confusing why maximum bitrate in Mediainfo is actually not the maximum, overall bitrate . . . .

Do you mean the real maximum bitrate that is in the video, if so this would be called the Peak bitrate see image below - this is the mp4 version (for the Internet) of the one I used in my example above.

As you can see above, the bitrate changes greatly throughout the duration of the video.

In this example - I could not use the previous m2ts file because the software used is old and does not support newer formats - the lowest bitrate is 2756 kbps and the peak 20923 kbps (pink graph), ie the peak rate is 7.6 x higher than the lowest (pink graph).

The Average bitrate (blue graph) is a true average and agrees with MediaInfo.

The encoder also over-rode the Maximum Bitrate setting I set (18000 kbps) many times because the detail in the source video and images was extremely fine as shown in the example below.

The Bitrate viewer is a useful tool, however I use it very rarely.

To round off this comment, the one tip that is frequently given is not to modify the export presets in MEP. They are already optimised for the various video formats and resolutions.

Changing these settings can result in actually making the video visually worse and also end up wasting a lot of time for very little, if any, gain.

HTH

John EB

 

 

Is Bitrate viewer accurate? It’s just I’ve read online that the information given can be inaccurate.

So, is it basically best to simply use only Mediainfo to check the bitrate and don’t use Windows at all? And does the maximum bitrate just mean the maximum bitrate that you set in the encoder?

And does the maximum bitrate just mean the maximum bitrate that you set in the encoder?

My take is that the encoding (and perhaps the analysis also) is a dynamic process and just because you set a maximum, especially with the complexities of MPEG encoding, it is conceivable that spikes will exceed the maximum set at times as in John's BR viewer example.

Also as John has stated:-

AFAIK the Maximum bitrate is included in the file header data so that the decoder can check whether the video is playable ie that it is not suddenly hit with a bitrate that is higher than its capabilities which can cause a crash.

I believe that a player can likely cope with small spikes above the allowable "standard" and the maximum is keeping it below the set figure for any sustainable period, which might cause a player to crash.

So, is it basically best to simply use only Mediainfo to check the bitrate and don’t use Windows at all?

I don't use Windows. Also Windows explorer shows a different file size to Windows>Properties>Detail....?

Something else - if you turn the file size in Bytes into bits and divide John's example by it's length in seconds then I get 13876kbps....?

Peter

@KenWicks

. . . . . I notice also that the data rate value in Windows is exactly the same value for maximum bitrate in Mediainfo . . . .

In the case of my example - this is not true - Explorer 19.03 Mb/s vs MediaInfo 24.0 Mb/s (I set this in the export dialog).

. . . . it’s a bit confusing why maximum bitrate in Mediainfo is actually not the maximum, overall bitrate . . . .

Do you mean the real maximum bitrate that is in the video, if so this would be called the Peak bitrate see image below - this is the mp4 version (for the Internet) of the one I used in my example above.

As you can see above, the bitrate changes greatly throughout the duration of the video.

In this example - I could not use the previous m2ts file because the software used is old and does not support newer formats - the lowest bitrate is 2756 kbps and the peak 20923 kbps (pink graph), ie the peak rate is 7.6 x higher than the lowest (pink graph).

The Average bitrate (blue graph) is a true average and agrees with MediaInfo.

The encoder also over-rode the Maximum Bitrate setting I set (18000 kbps) many times because the detail in the source video and images was extremely fine as shown in the example below.

The Bitrate viewer is a useful tool, however I use it very rarely.

To round off this comment, the one tip that is frequently given is not to modify the export presets in MEP. They are already optimised for the various video formats and resolutions.

Changing these settings can result in actually making the video visually worse and also end up wasting a lot of time for very little, if any, gain.

HTH

John EB

 

 

I did some tests comparing Mediainfo with Bitrate Viewer. In one of the screenshots that I've attached, you will see that in Bitrate Viewer the average and max (or peak) bitrates do not match with Mediainfo, however they are fairly close. But if you take a look at the other screenshot, you will see that the average and max bitrates, for another file, in Bitrate Viewer are not (as far as I can see) close to what Mediainfo says at all. Can anyone explain this?

@KenWicks

Hi

. . . . Bitrate Viewer the average and max (or peak) bitrates do not match with Mediainfo, however they are fairly close . . .

Within the limits of the mathematical calculations deriving the bitrates, the differences, 2 kbps and 81 kbps you are seeing in both cases are negligible.

To put these values in perspective the differences represent 0.0003 and 0.04 secs, ie they are equivalent of 0.008 and 1 frame of video, the longer the video the discrepancies are likely to be bigger as the difference error builds up.

In the case of the Peak rates not matching the Maximum bitrates - as I said in my last post these are 2 different measurements - they are not the same.

John EB

@KenWicks

Hi

. . . . Bitrate Viewer the average and max (or peak) bitrates do not match with Mediainfo, however they are fairly close . . .

Within the limits of the mathematical calculations deriving the bitrates, the differences, 2 kbps and 81 kbps you are seeing in both cases are negligible.

To put these values in perspective the differences represent 0.0003 and 0.04 secs, ie they are equivalent of 0.008 and 1 frame of video, the longer the video the discrepancies are likely to be bigger as the difference error builds up.

In the case of the Peak rates not matching the Maximum bitrates - as I said in my last post these are 2 different measurements - they are not the same.

John EB

Hi again, John,

So, does this mean that either Bitrate Viewer or Mediainfo are likely producing slightly inaccurate reports? And, please may you explain again the difference between maximum bitrate and peak bitrate?

@KenWicks

Hi

. . . . Bitrate Viewer or Mediainfo are likely producing slightly inaccurate reports? And, please may you explain again the difference between maximum bitrate and peak bitrate . . .

When comparing MediaInfo and Bitrate Viewer, or with any other bitrate viewers, the slight inaccuracy are so small you can consider them negligible - looking at it another way the differences we are talking about - you would never notice and difference in the video when playing it..

The difference between Maximum and Peak - I refer you back to your question and my response here and Peters comment here.

Added: in reference to Peters comment on converting MB/s to kbps or the reverse, in computer terms 'kilo' does not mean1000, it is 1024 eg. 1024 kbps = 1 Mb/s and the reverse

John EB

@KenWicks

Hi

. . . . Bitrate Viewer or Mediainfo are likely producing slightly inaccurate reports? And, please may you explain again the difference between maximum bitrate and peak bitrate . . .

When comparing MediaInfo and Bitrate Viewer, or with any other bitrate viewers, the slight inaccuracy are so small you can consider them negligible - looking at it another way the differences we are talking about - you would never notice and difference in the video when playing it..

The difference between Maximum and Peak - I refer you back to your question and my response here and Peters comment here.

Added: in reference to Peters comment on converting MB/s to kbps or the reverse, in computer terms 'kilo' does not mean1000, it is 1024 eg. 1024 kbps = 1 Mb/s and the reverse

John EB

 

 

 

 

Hi again,

So maximum bitrate is basically telling you what was set as the maximum bitrate in the encoder dialog?

@KenWicks

. . . . maximum bitrate is basically telling you what was set as the maximum bitrate in the encoder dialog . . . .

Correct.

John EB