Understanding video formats

[Brisn5757]

In the past I've always used 17Mbps as the video bit rate when recording a movie at 1920 x 1080.

I'm thinking of increasing the video quality by increasing the video bit-rate. I use PAL in my country.

I have a choice of:

17M/50i (which I'm currently using)
24M/25p
24M/24p (I think this is a motion picture frame rate)
28M/50p

50p suggests to me that I'm recording 50fps whole frames which could cause slow motion if played back at the normal 25fps rate.

There is very little information in the cameras manual (Panasonic G7) about these video formats so more information and advice would be most welcome thanks.

Brian

 

[Gary3000]

In the past I've always used 17Mbps as the video bit rate when recording a movie at 1920 x 1080.

I'm thinking of increasing the video quality by increasing the video bit-rate. I use PAL in my country.

I have a choice of:

17M/50i (which I'm currently using)
24M/25p
24M/24p (I think this is a motion picture frame rate)
28M/50p

50p suggests to me that I'm recording 50fps whole frames which could cause slow motion if played back at the normal 25fps rate.

There is very little information in the cameras manual (Panasonic G7) about these video formats so more information and advice would be most welcome thanks.

Brian

well, yes, 50p will be indeed slow if you play it back at 25fps, (and overkill if you convert it to 50i)

However, 50fps is actually the normal rate of video that you see on some PAL TV broadcasts (often at 1280x720) -= Pal 720p

yes, motion pictures are 24fps.

50i is interlaced video = ok to watch on a PAL TV, but no fun when uploaded to youtube, as it will have interlacing. I would avoid it

 

[Brisn5757]

In the past I've always used 17Mbps as the video bit rate when recording a movie at 1920 x 1080.

I'm thinking of increasing the video quality by increasing the video bit-rate. I use PAL in my country.

I have a choice of:

17M/50i (which I'm currently using)
24M/25p
24M/24p (I think this is a motion picture frame rate)
28M/50p

50p suggests to me that I'm recording 50fps whole frames which could cause slow motion if played back at the normal 25fps rate.

There is very little information in the cameras manual (Panasonic G7) about these video formats so more information and advice would be most welcome thanks.

Brian

well, yes, 50p will be indeed slow if you play it back at 25fps, (and overkill if you convert it to 50i)

However, 50fps is actually the normal rate of video that you see on some PAL TV broadcasts (often at 1280x720) -= Pal 720p

yes, motion pictures are 24fps.

50i is interlaced video = ok to watch on a PAL TV, but no fun when uploaded to youtube, as it will have interlacing. I would avoid it

Hi Gary.

That makes it difficult to chose as you have told me of the problems for all these video formats.

Brian

 

[a7sastro]

In the past I've always used 17Mbps as the video bit rate when recording a movie at 1920 x 1080.
......
17M/50i (which I'm currently using)
24M/25p
24M/24p (I think this is a motion picture frame rate)
28M/50p

50p suggests to me that I'm recording 50fps whole frames which could cause slow motion if played back at the normal 25fps rate.

........

Brian

well, yes, 50p will be indeed slow if you play it back at 25fps, (and overkill if you convert it to 50i)

However, 50fps is actually the normal rate of video that you see on some PAL TV broadcasts (often at 1280x720) -= Pal 720p

yes, motion pictures are 24fps.

50i is interlaced video = ok to watch on a PAL TV, but no fun when uploaded to youtube, as it will have interlacing. I would avoid it

Hi Gary.

That makes it difficult to chose as you have told me of the problems for all these video formats.

Brian

There seems to be a lot of confusion and over-complication here.

#1 higher bitrate doesn't necessarily bring you better quality, and it all depends on the content whether the differences will be noticeable.

#2 50i and 50p are BOTH 50fps. It's bizarre to think one will give you slow-mo on a 25fps timeline and the other won't. Do some more research if you both don't understand this concept.

Brian you yourself know what type of content most represents what you are doing, so do the test yourself, try out your different options and see from the delivery display if it is noticeable and which one looks the best.....

Do you usually use a 25fps timeline with your 50i footage?

For the record, you can always take 50p and convert it to 25p by dropping every other frame.

It's pretty much the same as combining the half-frames of 50i into 25 full frames.

Enjoy!

 

[Sean Nelson]

#2 50i and 50p are BOTH 50fps. It's bizarre to think one will give you slow-mo on a 25fps timeline and the other won't. Do some more research if you both don't understand this concept.

50i is really only 50 half-frames per second, not 50 frames per second. While you could in theory render it to a 25p timeline to produce slow motion, the result is going to look poor by comparison.

Brian you yourself know what type of content most represents what you are doing, so do the test yourself, try out your different options and see from the delivery display if it is noticeable and which one looks the best.....

Excellent advice, IMHO.

 

[a7sastro]

#2 50i and 50p are BOTH 50fps. It's bizarre to think one will give you slow-mo on a 25fps timeline and the other won't. Do some more research if you both don't understand this concept.

50i is really only 50 half-frames per second, not 50 frames per second. While you could in theory render it to a 25p timeline to produce slow motion, the result is going to look poor by comparison.

Brian you yourself know what type of content most represents what you are doing, so do the test yourself, try out your different options and see from the delivery display if it is noticeable and which one looks the best.....

Excellent advice, IMHO.

Sean,

re: half-frames.

Might want to read my entire post if you are going to quote parts of it and leave out other parts and restate the information that you left out as if I didn't mention it.

The focus was on slow-motion.As that was the subject of the question: "50p suggests to me that I'm recording 50fps whole frames which could cause slow motion if played back at the normal 25fps rate."

"Half-frames" is only a conceptualization and no one classifies 60i or 50i as "half-frames per second." Have you seen the abbreviation hfps? If you exported 50i or 60i out to individual still frames, they would come out as 50 or 60 individual captures in time, however the true data would have the comb look. Interpolation would fill in the missing lines..

Frames per second is an artifact from the motion picture industry where there were actual frames in the real of film. If interlacing existed, there would have been individual frames that would each contained comb like info....And each frame in the reel would pass through the projector at 50 or 60 times per second if it were to be called 50/60 fps. Of course cinema was always 24fps, etc. I only used it as an example....

And again I don't know why people are responding as if the OP wanted to do slow-mo, he is only intended better IQ from what is written.....Seems like he was trying to avoid a slow-motion look.....

 

[Sean Nelson]

#2 50i and 50p are BOTH 50fps. It's bizarre to think one will give you slow-mo on a 25fps timeline and the other won't. Do some more research if you both don't understand this concept.

50i is really only 50 half-frames per second, not 50 frames per second. While you could in theory render it to a 25p timeline to produce slow motion, the result is going to look poor by comparison.

Sean,

re: half-frames.

Sorry to rile you. I just wanted to correct something that struck me as misleading.

 

[Gary3000]

#2 50i and 50p are BOTH 50fps. It's bizarre to think one will give you slow-mo on a 25fps timeline and the other won't. Do some more research if you both don't understand this concept.

50i is really only 50 half-frames per second, not 50 frames per second. While you could in theory render it to a 25p timeline to produce slow motion, the result is going to look poor by comparison.

Sean,

re: half-frames.

Sorry to rile you. I just wanted to correct something that struck me as misleading.

Yes,. very misleading. because 50i is NOT 50fps! .. it's 25fps - or 50 "Interlaced fields", so you were quite proper in correcting him.
if you step thru 50i footage, one frame at a time, one second consists of 25 frames.

- AND for creative filming purposes, 50p will provide superior slow motion ability over 50i.

as for actual quality, and which bit rate to go with, it does get a bit confusing.
but generally the higher the bitrate - combined with the slower the fps, will generally produce the higher quality frame of video.- resulting in a better picture.

But per the OP's original question choices. if you plan to display/share your videos on youtube and online, stick with 24M/24p, or experiment with 50p for a more video-like look
if you plan to display on a PAL television, you can stick with those.. or try out the interlaced formats.

 

[Gary3000]

In the past I've always used 17Mbps as the video bit rate when recording a movie at 1920 x 1080.

I'm thinking of increasing the video quality by increasing the video bit-rate. I use PAL in my country.

I have a choice of:

17M/50i (which I'm currently using)
24M/25p
24M/24p (I think this is a motion picture frame rate)
28M/50p

50p suggests to me that I'm recording 50fps whole frames which could cause slow motion if played back at the normal 25fps rate.

There is very little information in the cameras manual (Panasonic G7) about these video formats so more information and advice would be most welcome thanks.

Brian

well, yes, 50p will be indeed slow if you play it back at 25fps, (and overkill if you convert it to 50i)

However, 50fps is actually the normal rate of video that you see on some PAL TV broadcasts (often at 1280x720) -= Pal 720p

yes, motion pictures are 24fps.

50i is interlaced video = ok to watch on a PAL TV, but no fun when uploaded to youtube, as it will have interlacing. I would avoid it

Hi Gary.

That makes it difficult to chose as you have told me of the problems for all these video formats.

Brian

The thing is that each format has it's purpose in the video world. (both in broadcast and online- as well as in the home on computer or on the television.

probably your best bet is to scour youtube for demonstrations of each to gain a better understanding of how they work and appear.

 

[Brisn5757]

In the past I've always used 17Mbps as the video bit rate when recording a movie at 1920 x 1080.

I'm thinking of increasing the video quality by increasing the video bit-rate. I use PAL in my country.

I have a choice of:

17M/50i (which I'm currently using)
24M/25p
24M/24p (I think this is a motion picture frame rate)
28M/50p

50p suggests to me that I'm recording 50fps whole frames which could cause slow motion if played back at the normal 25fps rate.

There is very little information in the cameras manual (Panasonic G7) about these video formats so more information and advice would be most welcome thanks.

Brian

Thanks all for your feedback on my post.

I did some video tests today and tried out various formats from two cameras.

I may have to stay away from 50i as it does not look too good due to the interlacing when panning, especially if there are near objects. I've used it in the past but may not have looked more critically at the results.

I wanted to try the 4K 100M 24p on the Sony RX100 IV but it said I needed a fast SD card. I'm using SDXC UHS-I cards. However the Panasonic G7 could record at 4K 100M 24p on the same card. There was a slight jerkiness on playback when panning in 4K video.
RX100 IV does offer 60M 24p in 4K which it then accepted my card.

I tried other modes such as 28M 50p and 20m 25p in MP4 on the Panasonic G7 camera but could not see any difference on playback on my computer screen, maybe slightly better quality in 28M.

I also tried AVC HD 28M 50p, 24M 24p on the G7 camera with no visual difference as well as 24M 25p and 17M 25p on the RX100 IV with no visual difference, but I suspect 24M offers slightly better quality on the RX100 IV camera and 28M is better on the G7 camera but I could not see any major improvement.

The RX100 IV also offers XAVC HD (1920x1080 Sony's own format with options such as 50m 50p, 50m 25p, etc but again I could not see any major difference.

I have a choice of AVCHD or MP4 for both cameras, but I'm likely to use the Panasonic G7 for video recording as it seems better suited for this.
I'm not certain at this age if AVCHD or MP4 is the best recording format to chose.

I'd be interested in what others choose to record video in other than 4K format.

Brian

 

[morski119]

I always use max available bitrate within the camera (for example 100Mbit with Fuji X-T2), regardless of frame rate.

Storage is cheap enough, and I always use memory cards with at least recommended card speeds or above.

After editing is done, I decide which bitrate to use for rendering. I usually stick with 17Mbit H264 for 30fps 1080p or about 40Mbit H264 for 30fps 4K. If I choose H265, then I use half of that.

Nothing scientific, I just don't trouble myself too much with some minor differences (visible or not) - above just works for me.

 

[LingoDingo]

If you're after the highest image quality with your Panasonic G7, you should shoot 4K video and transcode it down to 1080p in post. This will almost double the amount of detail in your 1080p image ( 1500+ lines of resolution versus 800+ lines of resolution ), and will also increase the amount of color information if transcoded properly. Yes it's a lot more work, but the increase in quality is quite substantial.

 

[joema1]

Brisn5757

...I'd be interested in what others choose to record video in other than 4K format.

I'd mainly suggest you avoid any interlaced format. It can frequently come back to cause problems when editing. I have answered innumerable questions from people who are confused about why their NLE is behaving a certain way when combining interlaced and progressive material, or why the playback software shows comb artifacts or why the artifacts are still there after uploading to Youtube.

You can avoid a lot of problems by (1) shooting everything progressive (2) using the same frame rate for an entire project ie not mixing two different frame rates, and (3) shooting everything in a given project the same aspect ratio, e.g, 16:9.

Re AVCHD vs MP4, I suggest not using AVCHD since the tree-oriented folder structure can be confusing. On Macs the AVCHD is displayed as a monolithic file bundle to try and prevent people from copying out bare video files, separate from the metadata in the other files.

4k cameras are sometimes optimized for 4k and when selecting 1080p the resolution may be less than the "name plate" resolution implies. E.g, they may use pixel binning to achieve the lower resolution which may degrade quality a bit. Other cameras may crop the sensor and scan a subset of the sensor which alters your composition.

I don't remember how the G7 handles this. We use the GH4 and GH5 but only 4k/29.97 8-bit at 100 mbps.

In general I recommend shooting 4k progressive at 100 mbps. You can always downsize that to 1080p later. However depending on your editing hardware and software, 4k could require proxy files to edit smoothly so there's an argument for 1080p if you don't really need 4k.

You aren't the only one to be confused about the terminology in the Panasonic manual: https://www.dpreview.com/forums/thread/3793570

 

[Brisn5757]

If you're after the highest image quality with your Panasonic G7, you should shoot 4K video and transcode it down to 1080p in post. This will almost double the amount of detail in your 1080p image ( 1500+ lines of resolution versus 800+ lines of resolution ), and will also increase the amount of color information if transcoded properly. Yes it's a lot more work, but the increase in quality is quite substantial.

The problem I have at the movement is a slight jitter when panning if using 4K video and also my Sony RX100 IV refuses to record in 4K 100M with my current SD card.

This is a problem as I brought a few 64 MB UHS-I SD cards for my holiday overseas. I do have a faster SD card that claims to be suitable for 4K video so I hope to try this card to see if the SD card is the problem. Apart from that 4K is likely to use up my SD card faster.

Looks like I may have to upgrade my old 2014 Adobe Premiere Pro as the only 4K support is for YouTube and if I render for 1080p the video has noise in the shadow areas.

Brian

 

[Brisn5757]

I always use max available bitrate within the camera (for example 100Mbit with Fuji X-T2), regardless of frame rate.

Storage is cheap enough, and I always use memory cards with at least recommended card speeds or above.

After editing is done, I decide which bitrate to use for rendering. I usually stick with 17Mbit H264 for 30fps 1080p or about 40Mbit H264 for 30fps 4K. If I choose H265, then I use half of that.

Nothing scientific, I just don't trouble myself too much with some minor differences (visible or not) - above just works for me.

If I go for my highest video rate that's not 4K then it must be 28M 50p in either AVCHD or MP4.

Brian

 

[Brisn5757]

Brisn5757

...I'd be interested in what others choose to record video in other than 4K format.

I'd mainly suggest you avoid any interlaced format. It can frequently come back to cause problems when editing. I have answered innumerable questions from people who are confused about why their NLE is behaving a certain way when combining interlaced and progressive material, or why the playback software shows comb artifacts or why the artifacts are still there after uploading to Youtube.

You can avoid a lot of problems by (1) shooting everything progressive (2) using the same frame rate for an entire project ie not mixing two different frame rates, and (3) shooting everything in a given project the same aspect ratio, e.g, 16:9.

Re AVCHD vs MP4, I suggest not using AVCHD since the tree-oriented folder structure can be confusing. On Macs the AVCHD is displayed as a monolithic file bundle to try and prevent people from copying out bare video files, separate from the metadata in the other files.

4k cameras are sometimes optimized for 4k and when selecting 1080p the resolution may be less than the "name plate" resolution implies. E.g, they may use pixel binning to achieve the lower resolution which may degrade quality a bit. Other cameras may crop the sensor and scan a subset of the sensor which alters your composition.

I don't remember how the G7 handles this. We use the GH4 and GH5 but only 4k/29.97 8-bit at 100 mbps.

In general I recommend shooting 4k progressive at 100 mbps. You can always downsize that to 1080p later. However depending on your editing hardware and software, 4k could require proxy files to edit smoothly so there's an argument for 1080p if you don't really need 4k.

You aren't the only one to be confused about the terminology in the Panasonic manual: https://www.dpreview.com/forums/thread/3793570

At the moment I have a problem using 4K so I'll move on to a 1080p format for now.
I have been recording in 1080p 17M 50i in the past but now what to try a higher video rate.

For the Panasonic G7 camera that reduces the choice to non interlaced formats:

AVCHD
28M 50p
24M 24p

MP4
28M 50P
20M 25P

Brian

 

[Brisn5757]

Brisn5757

...I'd be interested in what others choose to record video in other than 4K format.

I'd mainly suggest you avoid any interlaced format. It can frequently come back to cause problems when editing. I have answered innumerable questions from people who are confused about why their NLE is behaving a certain way when combining interlaced and progressive material, or why the playback software shows comb artifacts or why the artifacts are still there after uploading to Youtube.

You can avoid a lot of problems by (1) shooting everything progressive (2) using the same frame rate for an entire project ie not mixing two different frame rates, and (3) shooting everything in a given project the same aspect ratio, e.g, 16:9.

Re AVCHD vs MP4, I suggest not using AVCHD since the tree-oriented folder structure can be confusing. On Macs the AVCHD is displayed as a monolithic file bundle to try and prevent people from copying out bare video files, separate from the metadata in the other files.

4k cameras are sometimes optimized for 4k and when selecting 1080p the resolution may be less than the "name plate" resolution implies. E.g, they may use pixel binning to achieve the lower resolution which may degrade quality a bit. Other cameras may crop the sensor and scan a subset of the sensor which alters your composition.

I don't remember how the G7 handles this. We use the GH4 and GH5 but only 4k/29.97 8-bit at 100 mbps.

In general I recommend shooting 4k progressive at 100 mbps. You can always downsize that to 1080p later. However depending on your editing hardware and software, 4k could require proxy files to edit smoothly so there's an argument for 1080p if you don't really need 4k.

You aren't the only one to be confused about the terminology in the Panasonic manual: https://www.dpreview.com/forums/thread/3793570

At the moment I have a problem using 4K so I'll move on to a 1080p format for now.
I have been recording in 1080p 17M 50i in the past but now what to try a higher video rate.

For the Panasonic G7 camera that reduces the choice to non interlaced formats:

AVCHD
28M 50p
24M 24p
MP4
28M 50P
20M 25P

Brian

Hi joema1.

I've tried the interlace formats and there is a problem when scanning so I'm trying to get away from the interlaced mode and chose another video format.

I have a problem with 4K video at the moment which I'll try and solve later so at the moment I'm looking at another 1080p format.

Apart from the directory format are there any major differences between AVCHD and MP4?

Brian

 

[joema1]

For the Panasonic G7 camera that reduces the choice to non interlaced formats:

AVCHD
28M 50p
24M 24p
MP4
28M 50P
20M 25P

Of those I'd generally suggest 28M 50P MP4. However some cameras have better low light sensitivity at a lower frame rate. If low light performance is an issue I suggest testing 20M 25P MP4 vs 50P in a dark area.

Some cameras produce significantly better low light performance in 4k mode than in 1080p, e.g, the GoPro Hero5. That's another reason to evaluate 4k vs 1080p from a low light standpoint, assuming your SD card situation is resolved.

I'm surprised your SD card has a problem at 100 mbps, that is only about 12.5 MB/sec. The highest data stress is usually from a burst of raw stills, not H264 video. However video will simply not work if the card is too slow for the codec, whereas stills will just flush to the card slower.

 

[Brisn5757]

For the Panasonic G7 camera that reduces the choice to non interlaced formats:

AVCHD
28M 50p
24M 24p
MP4
28M 50P
20M 25P

Of those I'd generally suggest 28M 50P MP4. However some cameras have better low light sensitivity at a lower frame rate. If low light performance is an issue I suggest testing 20M 25P MP4 vs 50P in a dark area.

Some cameras produce significantly better low light performance in 4k mode than in 1080p, e.g, the GoPro Hero5. That's another reason to evaluate 4k vs 1080p from a low light standpoint, assuming your SD card situation is resolved.

I'm surprised your SD card has a problem at 100 mbps, that is only about 12.5 MB/sec. The highest data stress is usually from a burst of raw stills, not H264 video. However video will simply not work if the card is too slow for the codec, whereas stills will just flush to the card slower.

Thanks for the info joema1.

The Sony RX100 IV seems to refuse the 4K 100M mode as soon as I select this mode with a message that I need a different type of card. It must be able to read some info from the card to know what type of card I'm using. I think it suggested a UHS-3 SD card.

I'll try some low light video recording in the 50p and 25p formats.

Brian

 

[Gary3000]

For the Panasonic G7 camera that reduces the choice to non interlaced formats:

AVCHD
28M 50p
24M 24p
MP4
28M 50P
20M 25P

Of those I'd generally suggest 28M 50P MP4. However some cameras have better low light sensitivity at a lower frame rate. If low light performance is an issue I suggest testing 20M 25P MP4 vs 50P in a dark area.

Some cameras produce significantly better low light performance in 4k mode than in 1080p, e.g, the GoPro Hero5. That's another reason to evaluate 4k vs 1080p from a low light standpoint, assuming your SD card situation is resolved.

I'm surprised your SD card has a problem at 100 mbps, that is only about 12.5 MB/sec. The highest data stress is usually from a burst of raw stills, not H264 video. However video will simply not work if the card is too slow for the codec, whereas stills will just flush to the card slower.

Thanks for the info joema1.

The Sony RX100 IV seems to refuse the 4K 100M mode as soon as I select this mode with a message that I need a different type of card. It must be able to read some info from the card to know what type of card I'm using. I think it suggested a UHS-3 SD card.

I'll try some low light video recording in the 50p and 25p formats.

Brian

Yes, the Sony's are very picky about their memory cards and will refuse to record 4k unless it's a Class 10 U3 (even tho the U1's appear to be nearly as fast).
at least memory cards are cheap.