Hi, I'm new here and I've found out about the forum while searching on Google for the last month. There's so many information here and there and I'm getting confused the more I'm trying to understand. So I decided to write my own post so I can address my own questions. I hope this wont be a huge mess and that it'll be understandable.
First I want to give some context. I'm a music concert collector and trader, NOT a bootlegger. I've never sold anything and I buy what's available on DVD and Blu-ray. Most of my issues seem to be with telecined/interlaced DVDs while Blu-rays always seems to be progressive video content. Please correct me when I'm wrong because that whole post is what I understand and I'm here to learn the right information. So there may be written sentences as affirmation. I only did that to not always have to start my sentences with "if I understand correctly..." or "if I'm not mistaken...", you get the point!
What I understand is that there's a format difference between the original recorded content and what have been on television, recorded on home DVDs and commercial DVDs. Which complicates the encoding process for DVDs compared to Blu-ray that seems to be original progressive content as far as I can tell from the ones I own. I don't have a lot and haven't played with that media a lot so I may be mistaken and Blu-ray is interlaced too.
European theater content is recorded in 24 FPS progressive and television content is recorded in 25 FPS progressive. Television content (50i) is played back on the receiver at 50 fields/sec, 25 frames/sec. To get their progressive content on television whether it's 24/25 FPS it needed to be converted to interlaced video at 50 fields/sec, 25 frames/sec.
Does theater content shot at 24 FPS progressive was telecine to 50 fields/sec, 25 frames/sec while television content shot at 25 FPS was interlaced to 50 fields/sec, 25 frames/sec?
For the home DVD recorders it would make sense that everything would be recorded at 50 fields/sec, 25 frames/sec interlaced as it's what the television signal is.
For the commercial DVDs it would make sense to think that the same scheme is applied. Original theater content would be telecined and television content would be interlaced.
So am I right to say that the majority of the home recorded DVDs needs to be deinterlaced while commercial DVDs needs to be analyzed to see whether it's been telecined or interlaced?
I'll try to be the more precise but I have to precise that I'm much more confused about NTSC. Here we have a 60hz power system which makes the television signal (60i) at 60 fields/sec, 30 frames/sec. Well if that was true, id probably be less confused. It was right for black and white television but since the arrival of color television they were rushed to market color televisions as quickly as they could. Thing is that they had issues with transmission of the A/V signal. As they were in a rush they made the compromise to get a new standard of 29.97 FPS which would fix the problematic audio signal while having more bandwidth. Later they revealed that the audio issue wouldn't have been that much of an issue and that the signal could have stayed at 30 FPS.
So American theater content is recorded in 24 or 23.976 FPS progressive and television content is recorded in 29.97 FPS progressive. Television content (59.94i) is played back on the receiver at 59.94 fields/sec, 29.97 frames/sec. To get their progressive content on television whether it's 24/23.976/29.97 FPS it needed to be converted to interlaced video at 50 fields/sec, 25 frames/sec.
Does theater content shot at 24/23.976 FPS progressive was telecine to 59.94 fields/sec, 29.97 frames/sec while television content shot at 29.97 FPS was interlaced to 59.94 fields/sec, 29.97 frames/sec?
For the home DVD recorders it would make sense that everything would be recorded at 59.94 fields/sec, 29.97 frames/sec interlaced as it's what the television signal is.
For the commercial DVDs it would make sense to think that the same scheme is applied. Original theater content would be telecined and television content would be interlaced.
Again, am I right to say that the majority of the home recorded DVDs needs to be deinterlaced while commercial DVDs needs to be analyzed to see whether it's been telecined or interlaced?
Now id like to know how to de-interlace or de-telecine properly. I'm using Handbrake and everytime I'm searching for deep answers, I always end up on this forum reading that Handbrake have it's limits and that I should learn avisynth. I'm afraid to make the switch as I really like the queue which is really handy for DVDs where you have to cut content from chapters to chapters or simply have many DVDs to rip. I also like Handbrake for saving my custom presets and navigating the encoding options with a GUI is just more pleasant. Without to forget how great it is to crop with the preview window. I need to crop a lot of VHS that have been transferred to DVD.
At the time of writing this post, I have in mind to keep using Handbrake but that shouldn't be an issue for what I want to do.
HOW TO KNOW WHEN TO DE-INTERLACE OR DE-TELECINE?
Is there a tool in Handbrake? I guess not? So I read I have to check frame by frame and if 5 consecutive frames are 2 split fields it's interlaced and if there's 3 frames followed by 1 frame that have 2 split fields it's telecined. I've tried in VLC to first deactivate software deinterlacing and navigate frame by frame with the "E" key and I always got 2 split fields in each frame. So either I always got interlaced DVDs or VLC frame by frame function is broken. Maybe because most of my DVDs are music concerts recorded with DVD recorders.
HOW TO PROPERLY DETELECINE IN HANDBRAKE?
In the filters tab I have Default or Custom for the Detelecine filter. Do I need to use custom? If yes what do I write in that box?
In the video tab do I need to set the framerate to 25 FPS CBR for PAL content?
And what for NTSC content how do I know if the original content was shot at 24, 23.976 or 29.97 FPS? Simply by guessing like if it's a movie it's either 24 or 23.976 FPS and if it's content made for television it's 29.97 FPS? If I put the file in Media Info is there a way to validate that information?
HOW TO PROPERLY DEINTERLACE IN HANDBRAKE?
In the filters tab I have the "Interlace Detection" box which I read to always keep off as it can cause artefacts and issues. I also have a "Deinterlace" box with "Yadif" and "Decomb" options. I read that Yadif + Bob preset is the go to way.
In the video tab I'm confused as I've read so many different things. People say that you need to get back as close as possible to the original content therefore 24 or 23.976 FPS for a movie and 29.97 for television content. That's what I've always done for my whole library. Unfortunately at that time I didn't really understood what I was doing and I've saw that all my media in fast moving parts like drumsticks are still interlaced.
I've read that this is normal and it can't be 100% recovered once it's been interlaced or telecined.
I've also read that I could have doubled the framerate so for a 29.97 FPS DVD. I could have used 59.94 CBR instead of 29.97 CBR. So the Yadif filter would create individual frames from each interlaced fields. I haven't took that route because in my logic it didn't made sense to create computer generated full frames from incomplete fields and also because the original content is 29.97 FPS.
I also read that I shouldn't try to detelecine or deinterlace and let the player do the job as it's altering the quality negatively and that probably in the future the technology would get better. So doing it now with imperfect results from both methods said above would just reduce the quality. It makes sense on paper but I'm not sure that once you convert a DVD the flags that tells the player how to show the frames are still there? That would be problematic?
NTSC/PAL STORAGE AND PLAYBACK RESOLUTION
Another thing that confuses me is the storage and playback resolution. From what I understand the PAL DVDs compresses the data in a storage resolution of 720x576 which is played back at 768x576. I guess they had to compress somewhere to fit the higher resolution of PAL DVDs compared to the lower resolution NTSC (640x480) DVDs.
What doesn't make sense to me is the NTSC storage resolution at 720x480 (3:2 aspect ratio) to display at playback less data at 640x480. So when I convert NTSC DVDs I used to set the storage resolution the same as the playback resolution at 640x480. Have I lost data doing this because I can't see it?
I know it's not working in Handbrake. Since I've known about it, I'm using passthrough on all my tracks when it's possible otherwise I convert to AC3. Plex just converts to AAC when the destination device isn't compatible. No questions here, just wanted to say I'm aware of the AAC encoder issues.
I'm really sorry to write such a huge post with lots of questions. I felt it's the only way for me to learn and understand. Just by writing this post I've researched as I wasn't sure of many things and learned just by doing this. It took me 4 hours to write this post xD. I know your time and knowledge is valuable and that id be really lucky to have the chance to get a reply with answers to all my questions. Still I hope someone would like to teach me and help me be less confused.
Thanks a lot for whoever read this!
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Don't lose your nights, they're half your life.
Most of what you saw on SD TV was shot on film. The main exceptions were live TV (sports, news, morning shows, soaps...) which was shot as video at 59.94 fields per second in NTSC markets, 50 fields per second in PAL markets. Film was universally shot at 24p. For NTSC TV it was slowed to 23.976 fps and telecined to 59.94 fields per second for broadcast or recording. For PAL TV it was usually sped up to 25 fps and telecined to 50 fields per second for broadcast or recording. Beyond that you have a complex array of NTSC/PAL conversions, analog video being slowed or sped up for TV, and all kinds of mishandling.
Handbrake isn't great for anything beyond the most basic conversions. Basically film based material should be detelecined, video based material deinterlaced. For the former detelecine and reduce the frame rate to 23.976 fps for NTSC, 25 fps for PAL. For the latter use yadif and double frame rate (59.94 fps NTSC, 50 FPS PAL).
PAL can sometimes be phase-shifted, resulting in a video needing more than handbrake to restore
Best way to deinterlace stuff is by using QTGMC in Hybrid (after ripping dvd with MPEG2CUT2). You can also install avisynth, qtgmc and all its components. There are YouTube videos on doing it.
Some telecined content (like music videos) may have rough, interlaced transitions. In this case a decomber would help.
Handbrakde's Detelecine filter works fine for simple out-of-phase PAL. Be sure to set the frame rate to 25 fps.
Rather than giving us a bunch of misunderstood concepts, some samples from the collection might be more useful. And if you're serious about your hobby, you'll ditch Handbrake and switch to using AviSynth to prepare your encodes.
And, as s-mp implied, music videos are often the worst of the worst with which to work.
Am I allowed to post an example concert rip I've made so you can have an example?
My questions now is how bad it is that I've ripped everything with the deinterlace keeping original framerate so either 25 or 29.97 FPS. I guess it's too late? The end result doesn't seem that bad on the big screen with distance on the couch but on the computer screen I can see it. And definitely it's not as fluid. I hate myself!Don't lose your nights, they're half your life.
If he no longer has the original DVD he still might be able to fix some problems. For example a 24p movie encoded as a 30p MP4 could smoothed by decimating the duplicate frames. But he would have to decide if it's worth the time and effort, and whether the loss of quality from a recompression is worth the gain in smoother motion.
He said he's a collector and a trader so I'd guess he has a ton of these things from the 'best' available sources, as well as from other sources of all kinds. But, yes, the samples will tell the tale.
You're right I meant showing you an example of my encodes so you could tell the damage maybe by looking at it. As you said it's not needed since you guys confirmed me that I destroyed the quality of my sources.
As for keeping the best quality of everything it was simply impossible. I started collecting when I was 12 and it was all DVDs. Back then I found out that ripping the DVDs were much more interesting in order to keep the same quality (that's what I though few years ago, hardly distinguishable), rips were saving space, no more DVDs that stop working over time (trust me this happens), easier to trade on the internet and cost less cloud storage. It's only this year I started thinking about quality over quantity since I have the interest, I have unlimited cloud space and storage cost less nowadays. I still think DVDs are a fatality of the limitations of the time and that we should stop using them immediately. That's why I started ripping my commercial home DVDs which I still have. But all the trade DVDs had no value to me and I literally re-traded, give to friends or even trashed them without keeping a copy. You can judge me but it happened so I guess I just have to live with the fact my collection isn't as smooth as it could be.
Your explanation is rock solid and I've already saw the results in term of fluidity for my commercial DVDs. I'm still not sure this applies for home recorded DVDs. How does the data is handled? If the television broadcast is either 25 FPS or 29.97 FPS, will the home DVD record the flags to tell if it's been telecined or interlaced?* I'm kind of lost here.
* I'm aware that a lot of those trade DVDs aren't always home DVD recorders and sometimes they contains various sources re-encoded poorly. Here I'm really talking about a home recorder that records what's on television.
Thanks for your great help.Don't lose your nights, they're half your life.
All analog broadcast, cable, satellite, VHS, and Beta was interlaced. That was the only thing normal analog CRT TVs could display. All DVD recordings of such broadcasts were interlaced. Film sources would have been telecined to interlaced video, 59.94 fields per second or 50 fields per second, recorded digitally as 29.97 interlaced frames per second or 25 interlace frames per second.
Keep in mind that there was no such thing as a frame in analog video. Analog TV was a single continuous linear signal. An electron beam scanned across the screen, one line at at time, one field at a time. You never saw both fields at the same time. By the time a new field was being drawn the previous field had long faded away. In fact, by the time a new scan line was being drawn the previous scan line had nearly faded away. Your eyes are too slow to see this, of course. But watch this youtube video showing high speed footage of a CRT display being drawn (from about 2 to 4 minutes):
Wow that video was satisfying to watch!
So 100% of the home recorders DVDs needs to be de-interlaced and never detelecined?
What confuses me is that I though telecine was different than interlace. I read somewhere telecine have like 3 frames followed by 2 different frames, not so sure, but I remember it's a ratio of 3-2-3-2... and that telecine is all interlaced fields 1-1-1-1... But if you tell me telecined content is eventually interlaced I'm not sure I'm following up. Why do you telecine if you could have just interlace? I understand the process of slowing down 24p to 23.967p so it can fit to 29.97 in the interlacing process, but why do we telecine?
I though I understood and now I feel like I understood nothing. I'm really sorry to ask my newbie questions, I really want to learn.Don't lose your nights, they're half your life.
So nothing about compression.Don't lose your nights, they're half your life.
How film becomes NTSC video:
Film is shot at 24 frames per second. Somehow that needs to be converted (telecined) to 60 fields per second for analog video. The method that's usually used is to alternate between displaying film frames for three video fields, and two video fields. 2 film frames become 5 video fields, 24 film frames become 60 video fields.
A small portion of a video frame enlarge 8x, each 8x8 block represents one pixel:
[Attachment 60429 - Click to enlarge]
Four consecutive frames stacked horizontally, representing 4/24 (1/6) of a second:
[Attachment 60430 - Click to enlarge]
Those frames are projected, alternating between 3/60 second and 2/60 of a second per film frame. Ten of these 1/60 second frames stacked horizontally (1/6 second):
[Attachment 60431 - Click to enlarge]
The video camera transmits alternating top and bottom fields pulled out of those frames for broadcast:
[Attachment 60432 - Click to enlarge]
When viewed on TV this is what you saw over 1/6 second. Again, a small portion of the screen enlarged 8x, and slowed to 2 fps:
[Attachment 60433 - Click to enlarge]
Note that you didn't see little square blocks like this, but a fuzzy version of it.
When digitized, pairs of fields are woven together into frames, 10 analog fields becomes 5 video frames at 30 fps. Stacked horizontally:
[Attachment 60434 - Click to enlarge]
Notice that 3 of the 5 frames contain the original film frames, 0, 2, and 3. But two of them are a mix, film frame 0 and film frame 1, film frame 1 and film frame 2. Film frame 1 doesn't appear as a full frame anywhere in the five frames. But it's still possible to combine a field from each of those "interlaced" video frames to reconstruct film frame 1 -- as one of them has the top field from film frame 1 and the other has the bottom field. That is what an inverse telecine procedure does.
* black and white NTSC transmission was exactly 60 fields per second. When color transmission started it was changed to 59.94 fields per second for technical reasons. Most old analog B/W TVs were flexible enough to deal with the slightly slower frame rate. For purposes of this discussion I will use 60 and 30 rather than 59.94 and 29.97.
Last edited by jagabo; 25th Aug 2021 at 10:35.