I did some research on Canon progressive modes, the result is here:
http://www.elurauser.com/articles/ca...sive_modes.jsp
I hope I did not make too many errors.
24F, 24P, 25F, 25P, 30F, 30P explained
I did some research on Canon progressive modes, the result is here:
http://www.elurauser.com/articles/ca...sive_modes.jsp
I hope I did not make too many errors.
well that just convinced me to not buy a hv20.
Why the hell is a pulldown still necessary for footage recorded directly to disk with the HG10?
I can understand the HV20 needing pulldown removal, but the HG10? Damn.
Nice guide
I dont see the big problem whid the 25P function, but if I read it right, the PAL version is easyer to get the Progresive clips out right than the NTSC version.
Gear:
-Hv20 PAL -Rode VideoMic -FCS2
A few coments...
There is a small distinction between correct 25PsF (progressive segmented frame) footage and the "normal" way of showing 25fps content on TV for decades (i.e. 2-2 pulldown): When the content is intended for interlaced devices (2-2 pulldown), there should be vertical pre-filtering to minimise interlaced line twitter. When the content is genuine progressive, and is just wrapped in an interlaced stream for convenience (25PsF) there should be no vertical filtering.
Both rules are regularly broken. The HV20 does no vertical filtering, but uses 4:2:0 interlaced chroma (which ideally should never be used in 25PsF).
The RepeatFirstField flags are not "hints" - they define the correct output from the MPEG-2 stream. The correct output from a stream with "24p content flagged with RFF flags to bump it up to 60i" is 60i. You get 24p by ignoring the flags. The correct output would be 24p if there were no flags.
These flags can be used for many uses - bizarre pulldown patterns, efficient encoding of duplicate/still frames or fields etc. You should only ignore them if you're confident that you understand what effect this will have. With standard 24p-in-60i with flags content, you can be reasonably confidence that you'll get native 24p out in this manner. On a very wider range of MPEG-2 streams, you will get something quite unpredictable.
Finally, your starting paragraph said...
I have seen no evidence of "questionable results" from correct use of the free methods. The quality is no better or worse than the "costly" ones. The speed is another matter(!), but that is mainly because the "costly" methods are usually partnered to a proprietary near-lossy video codec. The free methods would give similar results in terms of speed if similarly partnered.Different schemes have been devised, from those that use dozens of free utilities in sequence, producing questionable results, to straighforward but costly ones.
Cheers,
David.
Thanks for the comments, guys! Much appreciated!
What about HDTV? Aren't HD televisions supposed to be progressive by nature, thus 2:2 pulldown can be done without filtering? I don't know, I am askingOriginally Posted by 2Bdecided
What about DVDs? When they say that 24p or 25p DVD content can be fully restored to 1080p without loss of resolution, is it not exactly true? Is content on a DVD prefiltered too despite being encoded as 24p/25p?
If I am not mistaken, 4:2:0 is a correct color encoding scheme according to HDV, the same scheme is used for 720p HDV too. So Canon could not do much here.
On the other hand, I've heard that Canon made its "F" modes part of the HDV standard. I don't know what changes these were, because HDV spec is not free, and even if you pay for it, they may not send it to you unless you are a manufacturer. Anyway, I suppose that features included by Canon's request were (a) 24F mode with 48i scanning, I believe that 48i was not part of HDV before; and (b) "progressive picture" and pulldown flags that effectively convert native interlaced video to PsF and allow to correctly recognize progressive video and restore it. But these are just my own assumptions.
So, with flags the correct output is supposed to be interlaced? Thanks, I will fix that.
Also, I am not exactly sure about XH output via Firewire. The doc states that it has true progressive output, while some users reported that they were able to capture and process video using interlaced preset, so I concluded that XH output contains pulldown flags.
I will remove the "questionable results" statement
In regards to the HG10, this is crazy. I am deciding on an HD camera for almost a year. First I wanted the HV20, then the HG10 came out, now the HF that has 30p. I would prefer 30p to 24p any day simply because it is easier to work with, I don't want to deal with pulldown removal, also 30p is faster thus is smoother. I don't get it why Canon stores interlaced video in a computer file.
On a side note, the pulldown flags are usually mentioned in regards to MPEG-2 only, but I assume that AVCHD has the same feature. It may happen, that transport layer of the MPEG-2 was singled out and reused in AVCHD, providing the same header/control/flagging functionality. Haven't researched this much.
Anyway, I downloaded two HF clips, one is 60i, another is 30p. The first one was loaded successfully by Vegas 8, the latter one was not, oops. I may only hope that this camera records and outputs true progressive video. I keep my fingers crossedI also hope that Sony will update Vegas to recognize Canon's new 30p.
The filtering is applied to the source, at the discretion of whoever is doing the capture/transfer/encoding. They can optimise vertical resolution to be sharper or softer, depending on whether they favour interlaced displays, progressive displays, or more likely whether they have a clue what they are doing.What about HDTV? Aren't HD televisions supposed to be progressive by nature, thus 2:2 pulldown can be done without filtering? I don't know, I am asking
What about DVDs? When they say that 24p or 25p DVD content can be fully restored to 1080p without loss of resolution, is it not exactly true? Is content on a DVD prefiltered too despite being encoded as 24p/25p?
The filtering can't be done by the display, since it's the legacy dumb CRTs without filtering that need it, and newer intelligent progressive displays that don't. So if you're going to tackle the problem, it has to be in the source itself.
4:2:0 is also correct for DVD, but there at least it can be progressive 4:2:0. True PsF gets used with 4:2:2 or 4:4:4 chroma, so there's no issue.If I am not mistaken, 4:2:0 is a correct color encoding scheme according to HDV, the same scheme is used for 720p HDV too. So Canon could not do much here.
As you hint later on, there seems to be some accommodation of true progressive within HDV on other machines, so it seems to be an intentional omission from the HV20. 24p-in-60i with flags is just as usable by consumers as 24p-in-60i without flags! Obviously the flags are desirable for professionals (or anyone who want to access true 24p easily), and the 4:2:0 progressive chroma that would allow would be hugely beneficial from a quality standpoint.
Cheers,
David.
David, thanks with filtering. Do I understand correctly, that pulldown (2:2 or 2:3, whatever) in analog TV is intended for interlaced TVs, pulldown in digital SD DVDs may or may not be inteded for interlaced TVs (whatever the produces decides), what about HD DVDs and Blu-ray disks? They are definetely inteded for progressive-capable devices, they are not analog, so there should NOT be any prefiltering for high-def disks?
When I thought I got it all sorted out, you are losing me again
Also, some compare the HV20 to the DVX100, and say that the DVX is easier to work with because it has flags. This is another point of confusion for me. The DVX records the same 24p-in-60i video as the HV20, so if I understand correctly, it should output it in the same way, with no flags, just because flags are not valid for interlaced video. How come that video from the DVX is recognized by 24p-capable NLEs as 24p? Or do they talk about 2:3:3:2 which is easier to recover and which is, apparently, supported by some higher-end NLEs, while 2:3 is not?
I got sidetracked (I am at work) and was going to say the same exact thing here. The HV20 and the DVX are basically similar in how they use 24p. People seem to forget before 2004 there were no editors that were capable of using 24p. And when the DVX came out...initially there was no support "at all"...just like when the HV20 first came out. People have been editing 24p within 60i for years. It's silly when people question if the HV20 is "real' 24p or not. The only difference is...well..Canon did not add the flags. But so what...it made things more difficult for us "at first"...but now everywhere you turn there is support for its 24p. So, currently, there is nothing difficult about the HV20's 24p....some people like to say that it is because they just don't really know what they are talking about....by the way....that last comment is not directed at anyone here..
No one can read the Gospels without feeling the actual presence of Jesus. His personality pulsates in every word. No myth is filled with such life...Albert Einstein
Ian, you are making the same kind of commend as David did, that interlaced MPEG-2 video can have pulldown flags. From what I've researched on the topic, it seems that only progressive video can have pulldown flags, but interlaced video does not have them. Interlaced is interlaced, just a sequence of fields. Are you saying that I am mistaken? Here is a quote from MainConcept MPEG-2 encoder documentation:
"The parameters under "Pulldown" convert 24 fps to 30 fps and it is supposed to be done only on progressive frame video (like film). The video encoder manupulates the TFF and RFF flags to convert 4 [progressive] frames into 5 [interlaced] frames."
They talk about encoding, but in case of a video camera, we should talk about decoding video coming from the camera and passing it along to an editing app, but basically it is the same thing, interlaced video is not supposed to have pulldown flags, progressive video does.
The MPEG-2 FAQ has this statement followed by a table of truth for flag combinations:
"repeat_first_field was introduced in MPEG-2 to signal that a field or frame from the current frame is to be repeated for purposes of frame rate conversion (as in the 30 Hz display vs. 24 Hz coded example above). On average in a 24 frame/sec coded sequence, every other coded frame would signal the repeat_first_field flag. Thus the 24 frame/sec (or 48 field/sec) coded sequence would become a 30 frame/sec (60 field/sec) display sequence. This processes has been known for decades as 3:2 Pulldown."
I would enormously appreciate if you explained what flags does interlaced DVX include that the HV20 video does not.
From the DVX-100 User's Manual: "Recorded video signals: 525i (NTSC). In the progressive mode, the signals are converted into the 525i system and recorded". So, the DVX records interlaced. But you've acknowledged this yourself.
From the FCP User's Manual: "Remove Advanced Pulldown (2:3:3:2) From MiniDV Sources: Check this box if you’re capturing from a DV-format source that used the 2:3:3:2 pull-down method to capture 24P video by fitting 23.98 fps video into a 29.97 fps stream. You want to remove the 2:3:3:2 pull-down to eliminate the redundant frame fields created by the pull-down so that you can edit true 24 (actually 23.98) fps progressive video." This paragraph cleanly says about removal of extra fields, but says nothing about flags.
My understanding is that FCP has been patched for video produced by DVX-100. Panasonic guarantees that video is written in chunks of 4 progressive frames, or 5 video frames, with cleanly defined structure, which surely helps. In fact, FCP does not even need to analyze incoming video, all it has to do is to delete every 3d frame out of every 5-frame video sequence. I bet this is how it works until someone proves that there are indeed "pulldown flags" in the interlaced video. I really want to make this issue clear for myself once and for all
It seems that the HV20 does not guarantee that video is written in fixed 5-frame chunks, just like the HG10. In this case, video has to be analysed, and simple removal of every 3rd frame will not work. It seems that FCP works for the DVX first because it is losless 2:3:3:2 pulldown, second because nothing has to be recombined, only one frame out of five has to be dropped, and third, because DVX guarantees 5-frame chunks, while the HV20 does not.
These issues can be solved, and Cineform is a good example of relatively inexpensive and clean solution, but the point is, that things could have been done better at the first place. Cineform offers solution to a problem that should not have existed. Canon at least could guarantee 5-frame sequences.
By the way, it seems that the HV30 dropped support for "F" modes, so it cannot be used as deck for XH camera anymore.
Last edited by Rumpelgeist; 2008 March 3rd at 17:05.
Where did you hear about this? That's bad news.
Taky, I read it on CCInfo, someone quoted HV30 features. I don't know where he got to read the manual, considering that he does not have the camera. The manual is not available on the Canon website either. Maybe it is not from the Manual. I don't want to spread the FUD, please just delete my message along with this one.
Also, feel free to delete my previous two messages, right after Ian's comment. Lots of words
Supported play back modes:1080/60i, 1080/24p, 1080/30F, 1080/24F, 1080/30p
CJ, thanks for confirming that. *phew*
what's the significance/meaning to all these?
Can someone tell me in laymen terms what’s the significance/benefits to each of these shooting modes of the HV20/HV30. I truly applaud Canon for providing the consumers with so many options - And i have voted for Canon with my wallet (instead of the Sony HC9). Just wish I understand them to be able to use them correctly. The one I read about frequently is 24P and people says it makes it look like film. Does it? What’s the significance and disadvantages to 24P then?
machoman, watch this clip from Friends: http://www.youtube.com/watch?v=iU39sqEQOms Compare "home video" in the Ross's house, which is how 60i looks like, and the regular show. I've read that the regular show was shot in 30p, not in 24p, but you still see the difference compared to 60i. The difference is still noticeable, even when watched on Youtube. If you don't see the difference in motion representation, then you don't need 24p or 30p
Most people feel the difference, though normal people usually cannot explain what exactly is different. Home video looks, well, like video. That is, too real. Of course, the camera work and lightning emphasize this "home video" look. The goal of 24p and 30p is to avoid this "too real" look, which greatly helps to "suspend the disbelief" so to speak.
Go to a store where they display new 120Hz TVs with motion interpolation, and take a look. Normal movies look like crappy cheap videos on these TVs. I would not even watch them for free. With 60Hz frame rate (even that these frames are artificially constructed) you immediately notice all the holes in the plot, how badly actors play and how stupid are their dialogs. All because the magic of 24p has been taken away
Last edited by Rumpelgeist; 2008 March 4th at 13:20.
These modes need special processing.
Thank-you for your reply.
And i'm beginning to think that what i've been doing with my Sony HC96 Standard Definition video through Sony Vegas 7 is not enough for the Canon HV20. I've shot at 24P, quite like the 'look' and have used Vegas to render but didn't do any special pulldown thingy and the end result of that is the produced file looks just as bad if not even worse than my standard definition videos. I'm reading more about these thing called pulldowns and such and think maybe i should employ them. Its sounding quite complicated.
I'M going to write to the PC Processing section of HV20.com to ask for advice on processing using Vegas.
Thanks Guys.
Last edited by machoman; 2008 March 4th at 16:51.
machoman...removing pulldown is not as complicated as you might think. If you are going to do it with the free method then there is a tutorial linked to Eugenia's site that will help you set up the necessary free software. Once you have the software setup correctly then it all becomes a "one click" process ..where you can also batch process all of your clips. The other way is basically buying a third party utility like Cineform to remove it automatically while capturing to your PC. There are other ways also....but my point to you is...it's not complicated at all. Don't believe the Hype.
Burning your material to DVD is not any different than what you might already be used to with your SD material.
No one can read the Gospels without feeling the actual presence of Jesus. His personality pulsates in every word. No myth is filled with such life...Albert Einstein
Your HC96 is capable of shooting 30p in PsF-style fashion. It is identical to how the HV30 records 30p, save the difference between SD and HD. With 30p you can load your video in 60i project and then select "progressive source" from the dropdown list. Same with 25p. This does not work with 24p.
Right, but you have to spend time, disk space, and you add yet another re-encode, though if you add effects or color-correct or use an intermediate codec, then added reencoding does not matter.
Ian, you mentioned the pulldown flags that HV20 is missing. According to what you said, DVX is has the flags. Could you explain what exactly did you mean?
That's all fine and dandy until it comes time to render to a physical medium for distribution. How are you going to guarantee 1080/30P playback from BD when that format is not supported in the current spec? Even if your NLE allows you to encode 1080/30P to BD, it MUST be flagged as 60i in order to remain compliant. So what happens now at playback time?
Is your BD player going to be smart enough to ignore the interlace flags and instead add 2:2 pulldown to your 30P material and push it out over HDMI at 1080/60P to your progressive flat panel display? I highly doubt it. I'd like to see this feature confirmed by a professional review before doing anything substantial with 1080/30P.
I have the same concern. Premiere CS3 won't even let me encode 1080p30 i n29.97fps (only 60i 30fps or 24p 23.976fps).
Aaron, you are right, it seems that there is no point in setting "interlaced" to "progressive" in project properties if output is going to be interlaced anyway. So why not to keep it interlaced? An NLE would not do anything with it, the burner would not do anything with it too. The only difference is when you preview full frame you will not get interlace jaggies.
This stuff will be recorded as 60i, this is what I meant in the previous post, because BD does not seem to support 30p. So the player has to recoginize 2:2 pulldown in 60i video and recover full 30p back. This is how 24p is sent and recovered to full HD, this is how 25p is sent and recovered to full HD. I don't see what's the deal with 30p, it should not be harder to handle it than 25p, which is done in 50Hz TVs and players.
There is no pulldown to add, it is all already there, 30p or 60i, same number of fields, nothing is changed besides processing.
I think that owners of 50Hz equipment could chime in, but so far I don't see any difference between 30p and 25p processing.
Yep, the player I bought has Silicon Optix chip, it is one of the best chips on the market that you can get for reasonable price. This player was tested by Secrets of Hi-Fi, and passed 2:3 and 2:2 cadence tests with flying colors. So my own personal videos will be covered. this player has other issues, namely compatibility with some Blu-ray disks, but this is irrelevant for this discussion.
On another hand, I would not distribute 30p if I wanted to ensure maximum possible quality on customer's equipment. Maybe in couple of years, when 30p hoopla with gather broader support from TV and players' manufacturers.
What do you mean? If I am not mistaken, 30F from your A1 should be 29.97 fps, not 30.0 fps, just to keep things simple with TV equipment. 29.97p or 29.97i should make no difference. Are you saying that Premiere does not allow to output as interlaced? I am really interested in what is happened there. I am also curious how those who live in PAL land, process 25p.
I'm using 30fps and 29.97fps interchangably to save keystrokes in typing.
In Adobe Media Encoder, if I export to to BluRay MEPG or BluRay H.264, I can only export 29.97 Interlaced, or 23.976 progressive. It will not let me select 29.97 progressive.
http://www.hv20.com/showthread.php?t=7406
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