OK folks, I have been all over the internet shouting at Sony to give the PXW-X70 a 100Mbp/s bit rate option.....

So, this weekend, I decided to do an AX100 codec test just to see what the real difference truly is. I shot the same scenes with the same exposure and just toggled files with the two different bit rates. I then did a split screen and made identical zoom and crops on both shots. These all have a 400% or more zoom so that we can really "pixel peep" these things so YouTube's crappy resolution doesn't get in the way.

Here is the test result:

https://youtu.be/dcS6KDKQYGA

I must say that I'm blown away at how similar these shots tested! On some, the 100Mbp/s was SLIGHTLY less blocky while on others, the 60Mbp/s appeared to have more noise reduction? The bottom line is that they don't look far away from each other at all...and this is REALLY strange.

Is Sony "padding" their 60Mbp/s codec to artificially "inflate" it to 100Mbp/s?

Is the Sony AX100 codec simply not able to "efficiently" encode 100Mbp/s to it's full potential?

In UHD, adding 40 megabits to 60 should encode ALLOT more bits deeper into the blacks. I realize that the mid-tones might not see allot more efficiency but the shadows SHOULD be getting those extra bits allocated to them. But here, this doesn't seem to be the case. Why?

I'd love to see similar tests form you fines folks out there. If you have an AX100, please take shots with both codec bitrates, combine them with a deep zoom-in and let's all take a look.

This is a very telling test result so far....very strange.

Your thoughts?

Cliff,

Dang, this is good. I like a good mystery story and this looks like one.
.
This is a very telling test result so far....very strange.

And, those are some very good questions.

Because the pictures look the same, I assume both cams were on a tripod so we could rule out any input from Image Stabilization.

Well done. "The proof is in the pudding" as they say.

Yes, I absolutely agree (I did raise a post before asking if anyone could see any difference). The only difference is that 100Mbps produces much bigger files. Another question would be does the 100Mbps stand up any better to colour grading than 60?

There is one very telling test that I have not done yet. That's 4K 60Mbp/s internal XAVC-S vs. 4K ProRes from the HDMI port.

By all rights, when compared side by side, the ProRes should look significantly better than 60Mbp/s.

If the two look exactly the exactly same? Wow...that could mean only one thing: The image quality "bottle neck" exits BEFORE the internal codec and BEFORE the HDMI port. In other words, the image quality is "limited" or "reduced" before it gets to the codec or HDMI port and there is nothing that can be done to improve it. (The image quality would be the same at 60Mbp/s, 100Mbp/s or ProRes)

Again....only further testing can prove this. But...this will be an excellent test to perform and could reveal some big internal processing AX100 "secrets".

Lets see....I don't want to jump to conclusions here but that will be a very important test.

EDIT - New info - Just did a side by side with internal XAVC-S 60MBp/s vs. 4K ProRes HG off the AX100's HDMI port. Good NEWS!...the ProRes looks significantly sharper in the shadows. It definitely has a very different noise structure and DOES hold detail in the shadows better. NOTE...Sony employs noise reduction into it's XAVC-S codec processing. The HDMI port does not have the noise reduction. As you know, Noise reduction softens the image. This is another reason why ProRes will look sharper. If you are using anything above 0db, with HDMI, you will need to add noise reduction.

Whew! I think I can put that concern to rest. The AX100's HDMI does seem to be pre-internal codec.

Only question now is: What is wrong with the AX100's XAVC-S codec? Why is 60Mbp/s and 100Mbp/s 99.9% identical???

I should think we also need to do a side-by-side of the AX100 60Mbps 4K, and the X70 60Mbps 4K.

Hi There,

It is not that surprising as the number of bit per second is enabling you to handle changes in the picture better, as the numbers goes up. If you have a totally static picture you would not be able to see any difference between a recording with 1 Megabit/S and a recording with 100 Megabit/S. Another thing is that AX100 and X70 is not running the same subversion of XAVC. X70 is using XAVC HD1080 Long GOP, and will probably use XAVC QFHD Long GOP in 4K version. AX100 is using XAVC S HD and XAVC S QFHD. This means that XAVC QFHD Long GOP at 60 Megabit/S might be equivalent to XAVC S QFHD at 100 Megabit/S. Both variants are variable bit rate, and the test recordings might not have demanded the full bandwidth available. XAVC is a very effective CODEC.Try to record waves at sea, to ensure most pixels changes between every frame.

The best
JOSS

Well? "XAVC-L" and "XAVC-S" are really not "codecs". They are really just industry standard MPEG h.264 codecs wrapped in .mp4 and .mxf containers. They follow the MPEG h.264 specification completely. There is nothing unique or anything that exceeds the h.264 spec.

Sony has created a file and folder structure and built an XAVC metadata structure to hold all kinds of info but this doesn't affect the h.264 codec quality. This is really what "XAVC" is.

Sony does have some neat processing tricks for "look ahead" VBR encoding but again the files are just pure h.264 as defined by MPEG long, long ago.

I'm going to do some side by side tests that contain allot more motion next weekend. Let's see how that looks. There is no reason why 60 and 100 Mbp/s should look so similar with high motion scenes....unless Sony "wants" it that way.

Hi There,

It is not that surprising as the number of bit per second is enabling you to handle changes in the picture better, as the numbers goes up. If you have a totally static picture you would not be able to see any difference between a recording with 1 Megabit/S and a recording with 100 Megabit/S.
Not necessarily true.

It depends how the inter-frame codec is implemented. What you say may have been true for earlier implementations, but nowadays such as XDCAM HD uses dynamic allocation of bitrate between the I-frames and difference frames - earlier inter-frame codecs tended to be fixed.

In simple terms it means that for static scenes the I frames get allocated a lot of bandwidth, difference frames not very much. With a lot of movement a far higher percentage of datarate gets allocated to the difference frames - at the expense of allocation to I-frames.

Assuming 50Mbs, and 50fps and a GOP of 50, then in an extreme example imagine the image is totally static - our ideal encoder may allocate to 50Mb to the I-frame and none to the difference frames. In the other extreme (every frame with a different image) it may allocate as much to every difference frame as to the I-frames - so 1Mb to every frame. Effectively it becomes an I-frame only codec!

Practically, the differences won't be anything like as extreme, both in terms of content or variation in allocation, but hopefully it helps to give an understanding of why the results will be so much better than a simpler encoder which always allocates x% to the I-frames and y% to difference frames.

And this is one reason why XDCAM gives so much better results than HDV, in spite of both being fundamentally MPEG2, and XDCAM EX not having that much higher a bitrate overall than HDV. Beware of drawing conclusions solely from headline statistics like bitrate.

There may well be a point of diminishing returns that only will be noticeable under certain shooting conditions. I'd expect that high motion would benefit from the higher bitrate, a "still motion" scene, not so much.

Not sure what you're monitoring the footage on, but even that may be a limitation as well - I've come to suspect that there are a few "glitches" where my cheap-o "monitor" hits the limits in color handling - nothing major, but certain colors in the red/hot pink spectrum seem to glitch a bit. Detail wise, there are many things that you won't be able to see on a 1080 screen no matter how much you zoom in, but will be obvious on a 4K screen.

There are many points along the chain where things can be degraded. I think this is why when I tried direct HDMI in to my TV/monitor, the onscreen image displayed from the RX10 (which is only 1080p) looked significantly better than the output from the "4K" AX33 I was evaluating... the starting point of the lens/sensor was obviously several notches "better" on the RX10 (as was the AX100).

Sony has created a file and folder structure and built an XAVC metadata structure to hold all kinds of info but this doesn't affect the h.264 codec quality. This is really what "XAVC" is.
Not true - such as H264 really only uniquely defines how a file is to be DECODED. It doesn't precisely define how it should be encoded as long as the result is able to be decoded according to the standard.

Hence manufacturers have quite a lot of flexibility in coder design, and are able to take advantage of new techniques as they develop - with XAVC Sony are implementing H264 at level 5.2. Which will give somewhat better quality than earlier implementations of H264 coding at the same bitrate and assuming all else equal.

Agreed David,

Yes, any company can use as many ENcoding tricks that they want. I have read that Sony has some key patents on their ENcoding techniques including tricks they have with VBR specifically.

Sony has full access to the existing MPEG h.264 toolset, like CALVC and CABAC and loop filters and blocking tools.The "look ahead" schemes and encoding is particularly powerful.

H.264 "profiles" like "baseline", "main", "high" and more contain higher and higher math and tool sets. Each level brings more tools galore! there are tons of tool sets. 8x8, 4x4 adaptive transform, slicing tools, quanitzation scaling, prediction techniques...blah blah...haha, it's allot of calculus and geometry!

"Levels" determine simple limitations for frame size, bitrate, frame rate parameters.

This is all wonderful but Sony can't put in new calculations that the h.264 specification can't understand. If Sony did that, than no h.264 complaint DEcoder would be able to make sense of it. One tiny "extra" or "unknown" calculation could literally "break" the entire file from playing back at all! Looking at H.265 HEVC,...this codec contains all the tools that H.264 has. In fact, h.264 is at the core foundation of HEVC! MPEG simply took h.264 and threw a TON of new math on top of it and raised the level restrictions way higher. No h.264 DEcoder can play any h.265 file because there is an enormous amount of "new" calculations that that poor h.264 DEcoder just doesn't understand.

Sony can do whatever they want on the ENcode but it must not "break" any of the h.264 calculations used for a fully complaint DEcode. So, the end result of all of Sony's XAVC efforts has an end result or "limitation" of being stuck on being 100% h.264 complaint.

But yeah,...ENcode to your hearts content but it's still gotta fit into the H.264 white paper limits on DEcode.

Detailed information about XAVC is on sony web page.

XAVC White Paper : United Kingdom : Sony Professional (http://www.sony.co.uk/pro/article/broadcast-xavc-white-paper-1211)

Hello,

my X70 has license for 4k, this is short samples doing fast panning. Original MXF files is for download here. Shutter speed is 1/50 in 25fps

Sony PXW-X70 4K 25p 1/50 #1 - YouTube

Sony PXW-X70 4K 25p 1/50 #2 - YouTube

Sony PXW-X70 4K 25p 1/50 #3 - YouTube

Original MXF 4k from PXW-X70
https://ssl.unlp.sk/x70/Clip0045.MXF
https://ssl.unlp.sk/x70/Clip0047.MXF
https://ssl.unlp.sk/x70/Clip0052.MXF

Thanks Zenes; unfortunately in Vegas Pro 11 the clips play at some 5 fps at Best/Full (watchable from Preview/Quarter and down). What the heck - this is Sony's own codec! Well, I guess proxies are the only way to edit - even a single track...

Something is terribly f***ed up in Vegas, because at Best/Full, CPU is only loaded up to 50% and GPU - up to 25%.

try use vlc, play this 4k smoothly on 4cores i5

Yeah, I know - VLC plays them back just fine, but one wants to edit, right?
Heck - Catalyst Browse plays them full speed!

Since they did not include the card structure, just the files, FCPX would not import these, but EditReady easily converted them to ProRes. Threw one into a 1080p timeline - played back easily even before rendering was finished. The ProRes plays back and edits beautifully, however I do have a 6TB Thunderbolt raid 0 on my 27" iMac.

Hello,

my X70 has license for 4k, this is short samples doing fast panning. Original MXF files is for download here. Shutter speed is 1/50 in 25fps

Sony PXW-X70 4K 25p 1/50 #1 - YouTube (https://www.youtube.com/watch?v=R999RVWtIV8)

Sony PXW-X70 4K 25p 1/50 #2 - YouTube (https://www.youtube.com/watch?v=yJ_a5ha2sug)

Sony PXW-X70 4K 25p 1/50 #3 - YouTube (https://www.youtube.com/watch?v=jo0aBUio8BY)

Original MXF 4k from PXW-X70
https://ssl.unlp.sk/x70/Clip0045.MXF
https://ssl.unlp.sk/x70/Clip0047.MXF
https://ssl.unlp.sk/x70/Clip0052.MXF

Where did you get your PXW-X70 4K license from?

Thanks Zenes; unfortunately in Vegas Pro 11 the clips play at some 5 fps at Best/Full (watchable from Preview/Quarter and down). What the heck - this is Sony's own codec! Well, I guess proxies are the only way to edit - even a single track...

Something is terribly f***ed up in Vegas, because at Best/Full, CPU is only loaded up to 50% and GPU - up to 25%.

Try Edius it will play them fine. I just use Vegas for audio editing the reason I got it originally !!!

Ron Evans

Where did you get your PXW-X70 4K license from?

Bought from official sony reseller in my region. It is little box with code, over sony webpage got license file based on s/n of camcorder.

Where did you get your PXW-X70 4K license from?
Clifton, would you upload more 4k footage maybe a minute or longer? Also your MXF files are giving an error when I try to download them.

Hi guys,

Maybe Piotr will need a faster cpu for this camera format? I was considering this camera, so tried the first clip here. (thanks Zenes).

I use Edius and my old i7-920 machine played the clip without stutters or frame drops but scrubbing was not smooth. This tells me what I already knew, that my old machine is out of it's depth with 4K. I had the same problem with 4K mov files from my GH4 so it's par for the course and I now have an i7-5960X machine.

With the new computer I found that in a 4K project Edius 7 can plays 3 streams of the MXF file consistently, without frame drops, scrubbing is smooth and precise. While playing, Win 7 task manager reports 16 logical cores at 45 - 95%.

Since I deliver 4K as HD I put the same clip four times into a 25p HD project, where for some odd reason Edius handled it even better! 4 streams, 16 logical cores at 91 - 98%.

Not tried adding filters yet but so far the camera format seems very editable, certainly no need to transcode, just need some power and a willing NLE... so just asking myself do I want the camera...

Bought from official sony reseller in my region. It is little box with code, over sony webpage got license file based on s/n of camcorder.

Wow, that means your region must have gotten it first.

It's not available anywhere else in the world yet.

Lucky!

Clifton, would you upload more 4k footage maybe a minute or longer? Also your MXF files are giving an error when I try to download them.

Maybe tomorow upload some more. Download server use SSL, has some certificate, try check correct time and date on your computer or use new web browser version, in this reasons is maybe some warning or errors on your side.

Zenes,

I tested your clips again on my friends super-fast computer and a 50" plasma HDTV (not UHD) and I must say something is terribly wrong with the quality - as if the clips were interlaced or something; there is a lot of jerkiness in panning and jagged lines. If that is the final quality of the troublesome X70 4k XAVC-L codec - the camera is seriously flawed...

PS. I can see the same artefacts in VLC, so it's not Vegas fault this time.

It's not available anywhere else in the world yet.
I got mine yesterday here in Germany. But I still waiting for the email from Sony

Oh, and one more thing:

When comparing all these new 4k cameras using Vegas or other NLE, we must remember that not all of them (or their codex) have been made equal - and when something doesn't work (or works worse than the rest of the bunch), it's not always Vegas Pro's fault.

As I have stated, 4k from the AX1/AX100 cameras plays back stunningly, with this "out-of-the-window" wow look. But I forgot about one more camera that also plays absolutely wonderful in Vegas: the JVC GY-HM200. Even though the native samples I have are in the dreaded MOV wrapper, they play full speed at Best/Full and the picture is amazing. Oh, and the 4k codec is 8 bit 420, but not overly compressed at 150 Mbps (the fps is 30p). Those clips play Best/Full even on my lousy laptop! If only the sensor was a tad bigger and better in low light...

Piotr

Thanks for providing the clips so I can test if my computer can handle them before getting into 4k.

I have been able to download the 3 mxf clips, import them into Premiere Pro CC and put them together on a 1080p and 3840p timelines. I've zoomed and split and sometimes the playback is a bit jerky, but that is because I am running out of RAM.

I tried a 3 clip multicam 4k sequence, but CPU bounced around 100% and RAM maxed out.

I don't know how I would go at 50p.

More RAM is next on the shopping list.

My computer is a DELL Vostro 470
i7-3770 3.4GHz
8GB RAM
NVIDIA GTX-660
1920 x 1080 monitor
Windows 7 Pro 64 bit

Zenes,

I tested your clips again on my friends super-fast computer and a 50" plasma HDTV (not UHD) and I must say something is terribly wrong with the quality - as if the clips were interlaced or something; there is a lot of jerkiness in panning and jagged lines. If that is the final quality of the troublesome X70 4k XAVC-L codec - the camera is seriously flawed...

PS. I can see the same artefacts in VLC, so it's not Vegas fault this time.

I try 2160p 30p in 1/50 shutter and looks panning much much better, 24p 25p not looks panning good in this resolution.

I try 2160p 30p in 1/50 shutter and looks panning much much better, 24p 25p not looks panning good in this resolution.

Agreed about 24p in our PAL area, but your clips are 25p and should look stunning on my 50" 200 Hz plasma. I edit HD in 25p and monitor the same way (the plasma is hanging on the wall in my editing studio, just in front and above me, so I watch it from some 1.5m distance).

In fact, 1080/25p material from EX1 or FS100 looks better than the 4k in the clips you provided - I hope Sony will issue yet another X70 firmware iteration soon to take care of these XAVC-L motion artefacts in 4k...

Now panning 2160 in 30p shutter 1/50

SONY PXW-X70 4K 30p 1/50 #1 - YouTube

SONY PXW-X70 4K 30p 1/50 #2 - YouTube

https://ssl.unlp.sk/x70/Clip0100.MXF
https://ssl.unlp.sk/x70/Clip0098.MXF

btw. new vegas out

Notable fixes/changes version 13.0 (Build 453)
-Fixed a bug that could cause the application to crash when using the Median or Min and Max video effects with an NVIDIA GPU.
-Fixed an issue that prevented Vegas Pro 13 from importing XAVC-L files recorded by the PXW-X70 camera.
-Fixed a bug that prevented XAVC long-GOP files rendered by Vegas Pro from playing on the PXW-X180 camera.
-Fixed an issue that caused the Wave Hammer Surround plug-in to run in Demo mode. The plug-in is now enabled in Vegas Pro.
-Improved playback performance for some MP4 video clips recorded by GoPro Hero cameras.

Much better panning in 30p, but only with VLC. Vegas still slow and jerky.

I think in Vegas again is problem with accelerating this 4k xavc. Try Sony Catalyst Browse if problem too.

@ Zenes: Could you upload the complete folder from the SDXC-card to test the function with Final Cut Pro X, but only the mxf isn`t recognized by FCP X, who needs the complete card-folder, so the testfiles only readable by Catalyst Browse. Thank you.

Four more 4k clips from X70 in directory structure

https://ssl.unlp.sk/x70/PRIVATE.ZIP (640MB)

https://ssl.unlp.sk/x70/Clip0153T01.JPG
https://ssl.unlp.sk/x70/Clip0120T01.JPG
https://ssl.unlp.sk/x70/Clip0114T01.JPG
https://ssl.unlp.sk/x70/Clip0115T01.JPG

Beautiful - were is the lake in Czech?

this is in Slovakia, High Tatras, Strbske pleso

I thought at first time tatra, because I read you are in Czech. It is a nice place there!

60Mbps vs 100Mbps on the AX100.

It's subtle, and it surprised me, but it's there. The 100mbps shows less aftifacting, macroblocking and smearing, in the darks especially. I pushed these images pretty far with by brightening up the mids considerably and adding a pretty intense LUT. Please note that I didn't try to make the images look good, but instead tried to show the differences in the bitrate by grading it intensely. See what I mean by looking at the brown box in shadow underneath the case on the shelf.

FWIW screen grabs attached. (can't attach the 100mbps wide for some reason, but you can see the differences in the CU)

So, I'm still not sure that the teeny weeny difference in quality is worth the doubling in file size going to 100mbps?

So, I'm still not sure that the teeny weeny difference in quality is worth the doubling in file size going to 100mbps?
I completely agree - unless of course your intention is to zoom in on your video by 500% :-)

Less artifacting when panning........I see it in the 100 Mps

Anyone have access to these files? I need to download them

*Edit* no longer needed