Working With AVCHD and XAVC Formats

[anachronon]

I have been considering the purchase of a digital video camera. However, the basic models that I have viewed, all use the AVCHD file format. Or, in the case of Sony, the XAVC format. Are these formats any good? In reviews, I saw folks complaining about the image quality. Is the quality problem in the codec? I would be interested in what folks have to say. Plus, is there a free conversion tool, to say, lossless AVI? Or, is it even worth the bother? Info on the internet has been painfully absent.

[ConsumerDV]

I have been considering the purchase of a digital video camera. However, the basic models that I have viewed, all use the AVCHD file format. Or, in the case of Sony, the XAVC format. Are these formats any good?

Any good compared to what? To VHS or to 8K RED RAW? This and this have been shot on a 12-year old AVCHD camcorder, no recompression on my side, YouTube obviously did recompress.

Info on the internet has been painfully absent.

Um, have you actually searched?

For broadcast you need at least 50 Mbit/s 4:2:2 MPEG-2 HD. AVC is about twice more efficient than MPEG-2. AVCHD as a subset of AVC supports 4:2:0 only, if this is important to you.

is there a free conversion tool, to say, lossless AVI

There is no "lossless AVI". AVI is a container, while lossy or lossless is a codec. You can re-rencode AVCHD as lossless of course, it has been around for more than fifteen years, there are tons of tools that support it.

I suggest using XAVC as a more modern implementation that has done away with the Blu-ray origins of AVCHD. In particular, XAVC-S is the popular Long-GOP consumer format.

[larioso]

As far as I understood, it's H.264 inside that is the actual codec anyway.

I use Canon DSLR with MP4 container and H264, and render to AVCHD 1080p in PowerDirector without any recoding.
PowerDirector has a marker in timeline which clips would be reencoded again.

I also have a Sony FDR-AX700 which do XAVC S HD directly and noticed nothing that I object to. And it pops right in with the rest of clips from DSLR 1080p.
Camera do XAVC 4K as well, but is above what I need anyway. I use also for slow and superslow motion up to 1000 fps. Above 250 fps there is degradation of quality a bit.

Just correct me if I am wrong, it just seems to me codec is H.264 or it would not work the way I described above.
Once picked out of container it is H264.

When you make a disk with AVC or XAVC though it is a special format with folders and stuff. But cool since you can do normal DVD media about 20 min film with that in 1080p(16 mbps as I recall). No need to mess with Bluray unless you need to for length.

[anachronon]

Thanks for the replies. Sorry about taking so long to get back. I had personal matters keeping my unavoidably detained.

Yes, AVCHD and XAVC are both H264. I found that in my research. I posted this question because of the bad camcorder reviews I read on Amazon. I figured it best to get opinions from folks who knew what they were talking about. I suspected that most of the bad Amazon reviews were due to "operator error". But, I wanted to be sure.

For AVCHD or XAVC, do i need and special capture/conversion software to import into Virtualdub or Adobe Premier (older version)?

I am considering a Sony CX-405. It is on the cheap end of the spectrum, but still seems to have the capabilities that I want, to get started (like wide-angle capability and adjustable white balance). I figured that this might be a good starting-point, until I see if I really want to get into video (my main focus is still photography). Does anyone have experience with this unit, and can offer advice? Is it "great choice", or "don't waste your money!"?

[ConsumerDV]

I have never tried loading AVCHD or XAVC into VirtualDub, I edit them in Vegas.

AVCHD was developed in parallel with Blu-ray. Either they did not want to think too much and adapted BD for camcorders, or they wanted to make a camcorder format that is compatible with BD. Either way, they introduced some limitations like file size that is limited to 2GB or 4GB depending on cluster size. If you shoot for long time you get several MTS files that you need to join. Tools offered by camcorder manufacturers are clunky, but they usually can join those segments into one large file. Other tools like tsMuxer can introduce A/V sync issues. Proper XAVC that records into MXF does not have this file size limit. XAVC-S - not sure, I think the file itself can be large as long as the file system allows and the manufacturer has it implemented.

The CX-405 is a small camcorder with a small sensor - bad sensitivity compared to a large-frame still camera, and deep DOF. Your experience will be vastly different compared to a still camera, and not very different than shooting with a smartphone. Maybe get a hybrid still/video camera like the GH4, GH5, A6500, newer Canon... I haven't followed new model development lately, as I keep using my old stuff. As you have probably noticed from my test videos above, 1080p60 looks VERY good. The particular Panasonic camcorder that I have is very sharp, but with the measly 28 Mbit/s bitrate the image sometimes breaks apart on busy scenes, especially if there is a lot of red color. A later model allowed 35 Mbit/s. Sony A6500 has 60 Mbit/s and 100 Mbit/s modes for XAVC-S. I think that 100 Mbit/s is overkill, but 60 Mbit/s is very nice.

AFAIK, the CX-405 does not allow full manual control of every exposure setting, but it has Exposure Lock. Focus can be locked too.

I am checking the specs... Is it a "world cam"? Apparently it can do both 60 Hz and 50 Hz modes. It looks that it can do 25i/25p/50p/30i/30p/60p, not bad. But it cannot do 24p, I don't know if you care.

[larioso]

There is some wisdom to "best camera for you is one that you bring with you".
So look at how you plan to record video.

There is a jump for CX-450 about $100, but you get touch screen and wifi too. You can remote control on a tablet or phone etc.
When you go up to AX series you have alternatives with optical view finder etc.

How you are going to use it - full daylight - and lcd screen?
How does that work for you?

For me it means wearing reading glasses while recording outdoors, and one point to make.
So optical view finder is a plus for me.

What type of editing are you going to do?
- what formats does it import?

Looking at editors I found that some just look at file extension and tell if you can import or not.
My Canons DSLR do MOV container making time lapse video, which some editors think is Quicktime just because of MOV extension and don't import unless Quicktime is installed on computer.
But since H264 inside anyway, in other editors it pops right in without Quicktime support.

So check out your chain of operations you are to use.
- shooting
- editing

If buying in a store, ask for a short film clip from that camera and test in editor of choice.
There might be reviews on YT as well that have links to film clips from that camera.

Have fun....

[rrats]

AVCHD is h264 powered. Hence it's name AVCHD

[anachronon]

What type of editing are you going to do?
- what formats does it import?


So check out your chain of operations you are to use.
- shooting
- editing

Those questions were the reason I was considering a cheap starter camcorder. 20-30 years ago, I did a lot of shooting with Hi8. But, that was another life. There were things to film, and editing wasn't really an option.

Today, I don't have the circle of friends and activities that I once had. I really don't know what videos i would shoot now. Hell, the camcorder could just end-up gathering dust on a shelf. That was why I was looking at cheap models. I would like to get an idea of what my video interest would be now---if any.

[ConsumerDV]

Why would not you start shooting videos with a smartphone - and editing on the smartphone as well, this can be fun! Then you can figure out whether you want/need more. You can shoot something like "Five for Five" - short vignettes with five shots five seconds each. It can be anything. Here I have four I dropped four clips on the timeline, trimmed and rendered, all on my phone using PowerDirector for Android. The quality is crap, but who cares. Still better than Hi8

[anachronon]

Why would not you start shooting videos with a smartphone - and editing on the smartphone as well, this can be fun! Then you can figure out whether you want/need more. You can shoot something like "Five for Five" - short vignettes with five shots five seconds each. It can be anything. Here I have four I dropped four clips on the timeline, trimmed and rendered, all on my phone using PowerDirector for Android. The quality is crap, but who cares. Still better than Hi8

I do not own a so-called "smart" phone, and never will. Those things track your every move, your every call, etc.

[ConsumerDV]

You are being tracked anyway: when you use a landline, when you use a non-smart mobile phone, when you browse the Net, when you drive (thousands of cameras around scanning license plates), when you walk around (cameras scanning and recognizing faces), when you buy groceries, when you deposit money in a bank, when you take money from an ATM, when you visit a doctor, when you get a credit line for a car, etc. Modern cars have built-in GPS, many camcorders have too, but the CX-405 does not have one, yay.

[dvd3500]

Watch the TV show "The Prisoner" and you will see how he predicted this in the late 60's,,,

[anachronon]

Back on the subject, perhaps someone could post a couple short, downloadable clips---one in AVCHD, and one in XAVC. That way, I could test what formats work with what software.

[ConsumerDV]

Here you are: 2 files, 200 MB in total. Shot with the Sony PJ670, which is similar to the CX405 - the same sensor and the lens. The link will expire in a week.

AVCHD (1080p60, 28 Mbit/s)

General
ID                               : 0
Format                           : BDAV
Format/Info                      : Blu-ray Video
File size                        : 72.3 MiB
Duration                         : 23s 35ms
Overall bit rate                 : 26.3 Mbps
Maximum Overall bit rate         : 28.0 Mbps

Video
ID                               : 4113 (0x1011)
Menu ID                          : 1 (0x1)
Format                           : AVC
Format/Info                      : Advanced Video Codec
Format profile                   : High@L4.2
Format settings, CABAC           : Yes
Format settings, ReFrames        : 2 frames
Format settings, GOP             : M=1, N=30
Duration                         : 23s 6ms
Bit rate mode                    : Variable
Bit rate                         : 24.8 Mbps
Maximum bit rate                 : 26.0 Mbps
Width                            : 1 920 pixels
Height                           : 1 080 pixels
Display aspect ratio             : 16:9
Frame rate                       : 59.940 fps
Color space                      : YUV
Chroma subsampling               : 4:2:0
Bit depth                        : 8 bits
Scan type                        : Progressive
Bits/(Pixel*Frame)               : 0.200
Stream size                      : 68.0 MiB (94%)

Audio
ID                               : 4352 (0x1100)
Menu ID                          : 1 (0x1)
Format                           : AC-3
Format/Info                      : Audio Coding 3
Mode extension                   : CM (complete main)
Duration                         : 23s 8ms
Bit rate mode                    : Constant
Bit rate                         : 448 Kbps
Channel(s)                       : 6 channels
Channel positions                : Front: L C R, Side: L R, LFE
Sampling rate                    : 48.0 KHz
Stream size                      : 1.23 MiB (2%)

Text
ID                               : 4608 (0x1200)
Menu ID                          : 1 (0x1)
Format                           : PGS
Duration                         : 22s 457ms

XAVC-S (1080p60, 50 Mbit/s)

General
Format                           : XAVC
Codec ID                         : XAVC
File size                        : 113 MiB
Duration                         : 18s 18ms
Overall bit rate                 : 52.6 Mbps

Video
ID                               : 1
Format                           : AVC
Format/Info                      : Advanced Video Codec
Format profile                   : High@L4.2
Format settings, CABAC           : Yes
Format settings, ReFrames        : 2 frames
Format settings, GOP             : M=1, N=30
Codec ID                         : avc1
Codec ID/Info                    : Advanced Video Coding
Duration                         : 18s 18ms
Bit rate mode                    : Variable
Bit rate                         : 50.6 Mbps
Width                            : 1 920 pixels
Height                           : 1 080 pixels
Display aspect ratio             : 16:9
Frame rate mode                  : Constant
Frame rate                       : 59.940 fps
Color space                      : YUV
Chroma subsampling               : 4:2:0
Bit depth                        : 8 bits
Scan type                        : Progressive
Bits/(Pixel*Frame)               : 0.407
Stream size                      : 109 MiB (96%)

Audio
ID                               : 2
Format                           : PCM
Format settings, Endianness      : Big
Format settings, Sign            : Signed
Codec ID                         : twos
Duration                         : 18s 11ms
Bit rate mode                    : Constant
Bit rate                         : 1 536 Kbps
Channel(s)                       : 2 channels
Sampling rate                    : 48.0 KHz
Bit depth                        : 16 bits
Stream size                      : 3.30 MiB (3%)

[anachronon]

Thanks Consumer DV. I have downloaded those files. I will play with them in a couple days.

[ConsumerDV]

You are welcome. Here are two more for good measure.

1080p24

ID                               : 1
Complete name                    : H:\avchd\00000.MTS
Format                           : BDAV
Format/Info                      : Blu-ray Video
File size                        : 24.3 MiB
Duration                         : 15s 918ms
Overall bit rate                 : 12.8 Mbps
Maximum Overall bit rate         : 18.0 Mbps

Video
ID                               : 4113 (0x1011)
Menu ID                          : 1 (0x1)
Format                           : AVC
Format/Info                      : Advanced Video Codec
Format profile                   : High@L4.0
Format settings, CABAC           : Yes
Format settings, ReFrames        : 4 frames
Format settings, GOP             : M=3, N=12
Duration                         : 15s 348ms
Bit rate mode                    : Variable
Bit rate                         : 11.9 Mbps
Maximum bit rate                 : 16.8 Mbps
Width                            : 1 920 pixels
Height                           : 1 080 pixels
Display aspect ratio             : 16:9
Frame rate                       : 23.976 fps
Color space                      : YUV
Chroma subsampling               : 4:2:0
Bit depth                        : 8 bits
Scan type                        : Progressive
Bits/(Pixel*Frame)               : 0.240
Stream size                      : 21.8 MiB (90%)

Audio
ID                               : 4352 (0x1100)
Menu ID                          : 1 (0x1)
Format                           : AC-3
Format/Info                      : Audio Coding 3
Mode extension                   : CM (complete main)
Duration                         : 15s 488ms
Bit rate mode                    : Constant
Bit rate                         : 384 Kbps
Channel(s)                       : 6 channels
Channel positions                : Front: L C R, Side: L R, LFE
Sampling rate                    : 48.0 KHz
Video delay                      : -83ms
Stream size                      : 726 KiB (3%)

1080i30

ID                               : 1
Complete name                    : H:\avchd\00017.MTS
Format                           : BDAV
Format/Info                      : Blu-ray Video
File size                        : 84.3 MiB
Duration                         : 45s 462ms
Overall bit rate                 : 15.5 Mbps
Maximum Overall bit rate         : 18.0 Mbps

Video
ID                               : 4113 (0x1011)
Menu ID                          : 1 (0x1)
Format                           : AVC
Format/Info                      : Advanced Video Codec
Format profile                   : High@L4.0
Format settings, CABAC           : Yes
Format settings, ReFrames        : 4 frames
Format settings, GOP             : M=1, N=30
Duration                         : 44s 911ms
Bit rate mode                    : Variable
Bit rate                         : 14.5 Mbps
Maximum bit rate                 : 16.8 Mbps
Width                            : 1 920 pixels
Height                           : 1 080 pixels
Display aspect ratio             : 16:9
Frame rate                       : 29.970 fps
Color space                      : YUV
Chroma subsampling               : 4:2:0
Bit depth                        : 8 bits
Scan type                        : Interlaced
Scan order                       : Top Field First
Bits/(Pixel*Frame)               : 0.234
Stream size                      : 77.8 MiB (92%)

Audio
ID                               : 4352 (0x1100)
Menu ID                          : 1 (0x1)
Format                           : AC-3
Format/Info                      : Audio Coding 3
Mode extension                   : CM (complete main)
Duration                         : 45s 24ms
Bit rate mode                    : Constant
Bit rate                         : 384 Kbps
Channel(s)                       : 6 channels
Channel positions                : Front: L C R, Side: L R, LFE
Sampling rate                    : 48.0 KHz
Video delay                      : -67ms
Stream size                      : 2.06 MiB (2%)

Text
ID                               : 4608 (0x1200)
Menu ID                          : 1 (0x1)
Format                           : PGS
Duration                         : 44s 480ms
Video delay                      : -67ms