Which codec/container makes lossless video editing possible?

[ilimitus]

I currently use VirtualDub to edit all my videos and for videos that can't directly be opened by VirtualDub I use avidemux to save as raw avi => and then open with VDub. Or Frameserve (avisynth) to Vdub if avidemux/direct vdub causes audio sync issues.

I then use StaxRip to encode to DivxPlus/X264 with MKV container. The problem is that if I want to re-edit the video in the future (with virtualdub), I have to re-encode with Staxrip, which means loss of quality.

Instead of using DivXPlus/Mkv, is there a codec/container that I can encode my videos with and allow future lossless editing? (Ex: Mpeg2? and frameserve edit into Vdub back to Mpeg2 w/out re-encoding?)- I don't know if this is remotely possible but just an ex. of what I'm trying to do.

Is this possible? If so which codec/container and editing software?

[hech54]

Although I don't fully understand your point...I use HuffyUV out of AviDemux to later open in VDUB(if necessary). I'm not sure what I'm doing is correct or the best....but it works for me.
I do know that audio sync issues are not the fault of the program(like AviDemux)....sync issues are caused but cutting in the wrong place....IE....your fault.

[PuzZLeR]

Not sure what you mean by "editing" but if it's only cuts, joins, and even fades, we are not far from having editors that will handle H.264 video in frame-accuracy for such tasks. Soon, you will not need an intermediary format, or even VirtualDub which is dependent on the VFW format. (But maybe you may have to remux to a container other than MKV, which would be lossless anyway).

As far as MPEG-2 is concerned, there are several great editors today that edit it losslessly (save for the very few frames close to the cuts and joins) such as VideoReDo, Womble and TMPGEnc MPEG Editor. However, I'm sure you realize that converting to MPEG-2 is lossy. But, assuming SD, 8000kbps MPEG-2 with a good MPEG-2 encoder is usually very close to the source in transparency.

You can also look into CineForm, which can be handled by VirtualDub. It's not small, but it's much smaller than lossless formats. It's not lossless in theory, but visually lossless. Professionals use this for edits and to archive source afterwards.

But the best advice I can give you is to keep the true Source. This alone made this hobby so much easier for me decision-wise since target formats change all the time. Keeping a separate copy of the Source always ensures the highest quality options in the future.

[ilimitus]

Not sure what you mean by "editing" but if it's only cuts, joins, and even fades, we are not far from having editors that will handle H.264 video in frame-accuracy for such tasks. Soon, you will not need an intermediary format, or even VirtualDub which is dependent on the VFW format. (But maybe you may have to remux to a container other than MKV, which would be lossless anyway).

As far as MPEG-2 is concerned, there are several great editors today that edit it losslessly (save for the very few frames close to the cuts and joins) such as VideoReDo, Womble and TMPGEnc MPEG Editor. However, I'm sure you realize that converting to MPEG-2 is lossy. But, assuming SD, 8000kbps MPEG-2 with a good MPEG-2 encoder is usually very close to the source in transparency.

You can also look into CineForm, which can be handled by VirtualDub. It's not small, but it's much smaller than lossless formats. It's not lossless in theory, but visually lossless. Professionals use this for edits and to archive source afterwards.

But the best advice I can give you is to keep the true Source. This alone made this hobby so much easier for me decision-wise since target formats change all the time. Keeping a separate copy of the Source always ensures the highest quality options in the future.

PuzZLeR, Thank you for your reply.

I agree with your advice to always keep source/original files of best videos although it still would be nice to be able to re-edit my mpeg4's/DivxPlus (lossless) in the future.

Yes when I say editing I mean cutting, joining, fading. And I am sort of new to this so please correct me if I am wrong with any points.

So currently, any "lossless edible" codec (Ex: Mpeg2, Cineform) would have a larger file than "non-lossless edible" codecs have (Ex: Mpeg4/X264/DivxPlus).
For example: 700 MB mpeg4/divxPlus VS 4000MB Mpeg2

When you say that soon we will have editors that handle H.264 (mpeg4/divxplus/x264) in frame-accuracy, you mean in be able to edit and save them in a lossless way? For ex. something like this work? www.fame-ring.com "..H.264 AVCHD MPEG2 frame accurate cutter without re-encoding.."

If not, is there a better example, link or article capable of lossless H.264/Mpeg4 editing you mention?

And would MP4 container be better suited for this if not MKV? or what container would you suggest?

[ilimitus]

Although I don't fully understand your point...I use HuffyUV out of AviDemux to later open in VDUB(if necessary). I'm not sure what I'm doing is correct or the best....but it works for me.
I do know that audio sync issues are not the fault of the program(like AviDemux)....sync issues are caused but cutting in the wrong place....IE....your fault.

Hech54, Thank you for your suggestion.

Yes I am semi-aware of that , since I noticed certain videos (WMV, Mpeg2) are maybe 25% of the time out of sync and certain other videos (Avi), are rarely out of sync. I also notice that if an WMV is out of sync in Avidemux, I can use VDub for the audio sync to work (and vice versa) or framework/avisynth to Vdub.

Okay HuffyUV, I am assuming this is a larger file compared to Mpeg4 (Xvid/X264/DivXPlus)? Just like Mpeg2 and Cineform and the like(too large for my purposes)? So I am correct that there is no such format that is comparable (in compression ratio and quality) as Mpeg4? And will have to wait until Mpeg4/H.264 frame accurate editors arrive to achieve my goal?

I am not well versed in editing, encoding, and I had to learn this through trial and error. would you say my approach is good? Can I improve it in any way?

1. Original video=> Vdub editing=> Raw Avi
(Original video=> Avidemux=> Raw Avi=> VDub=> Raw Avi) - for audio sync issues, etc

2. Raw Avi => StaxRip Encoding=> DivXPlus/Mp4 container (CRF 18-20)
(DivXPlus/Mp4 = Great compression and Quality)

3. (Future) DivXPlus/Mp4 => Lossless/Frame-accurate DivXPlus/Mp4 editing=> Re-edited DivXPlus/Mp4 Video

[poisondeathray]

just to clarify, your #3 isn't necessarily lossless when doing cut type editing (with something like videoredo4 beta)

divx avc uses Long GOP compression, so any time you make a cut within a GOP (not directly preceding an I-frame) , The software would have to re-encode the entire GOP. I think DivXPlus preset uses GOPlength of 95, so at minimum those frames around the cutsite would have to be re-encoded

Other types of editing require re-rendering the at least affected segments (e.g. if you use an overlay or transition, those segments would require re-encoding). If you did color correction adjustments like levels, the entire file would incur generation loss

[hech54]

This thread here should also help:
https://forum.videohelp.com/threads/331192-No-Huffyuv-Codec-under-VirtualDub-Compression

[ilimitus]

just to clarify, your #3 isn't necessarily lossless when doing cut type editing (with something like videoredo4 beta)

divx avc uses Long GOP compression, so any time you make a cut within a GOP (not directly preceding an I-frame) , The software would have to re-encode the entire GOP. I think DivXPlus preset uses GOPlength of 95, so at minimum those frames around the cutsite would have to be re-encoded

Other types of editing require re-rendering the at least affected segments (e.g. if you use an overlay or transition, those segments would require re-encoding). If you did color correction adjustments like levels, the entire file would incur generation loss

Hmmm I do not understand GOP compression, and GOPlength in regards to Divxplus, but essentially I would not be able to do lossless editing with a finished DivXPlus/Mp4 video? (since it requires re-encoding)

If not DivXPlus, is there a Mpeg4/H.264 codec better suited for this purpose? X264? DivX, Xvid?

[poisondeathray]

Hmmm I do not understand GOP compression, and GOPlength in regards to Divxplus, but essentially I would not be able to do lossless editing with a finished DivXPlus/Mp4 video? (since it requires re-encoding)

If not DivXPlus, is there a Mpeg4/H.264 codec better suited for this purpose? X264? DivX, Xvid?

None of them. They are not editing formats, they are end delivery formats. None of the ones you listed are "edit friendly" in their usual usage, unless you use GOP length of 1 (ie. I-frame only). This significantly impairs compression efficiency.

If you want to do farther edits, do it on the original as suggested earlier. Save the original always

Or use a lossless codec (expect filesizes 10-20x larger)

Also, frameserving (by any method) serves uncompressed video, so you always have to re-encode when frameserving

[hech54]

Hmmm I do not understand GOP compression, and GOPlength in regards to Divxplus, but essentially I would not be able to do lossless editing with a finished DivXPlus/Mp4 video? (since it requires re-encoding)

If not DivXPlus, is there a Mpeg4/H.264 codec better suited for this purpose? X264? DivX, Xvid?

None of them.

Exactly. Encoding to these formats reduces the quality(sometimes DRASTICALLY) and you NEVER get it back. This is not a ZIP file you are dealing with. Once the quality is gone....it is GONE.

[ilimitus]

Hmmm I do not understand GOP compression, and GOPlength in regards to Divxplus, but essentially I would not be able to do lossless editing with a finished DivXPlus/Mp4 video? (since it requires re-encoding)

If not DivXPlus, is there a Mpeg4/H.264 codec better suited for this purpose? X264? DivX, Xvid?

None of them. They are not editing formats, they are end delivery formats. None of the ones you listed are "edit friendly" in their usual usage, unless you use GOP length of 1 (ie. I-frame only). This significantly impairs compression efficiency.

If you want to do farther edits, do it on the original as suggested earlier. Save the original always

Or use a lossless codec (expect filesizes 10-20x larger)

Also, frameserving (by any method) serves uncompressed video, so you always have to re-encode when frameserving

Hmmm I do not understand GOP compression, and GOPlength in regards to Divxplus, but essentially I would not be able to do lossless editing with a finished DivXPlus/Mp4 video? (since it requires re-encoding)

If not DivXPlus, is there a Mpeg4/H.264 codec better suited for this purpose? X264? DivX, Xvid?

None of them.

Exactly. Encoding to these formats reduces the quality(sometimes DRASTICALLY) and you NEVER get it back. This is not a ZIP file you are dealing with. Once the quality is gone....it is GONE.

Okay I never knew mpeg4/H.264 encoding can cause such destruction to video files.

First I don't know if I made it clear but when I am talking about visually lossless, I mean to be able to edit and save without noticing the difference visually. (Maybe retaining 99% of quality visual wise). So I do not mean actual 100% lossless, but nevertheless 100% is better than 99%.

So basically from your post, there is no way to lossless edit a Mpeg4/H.264(DivXPlus,X2264,Xvid) video. (unless you use GOP length of 1). But what about future editors that will handle H.264 video in frame-accuracy as PuzZLeR talks about?

Not sure what you mean by "editing" but if it's only cuts, joins, and even fades, we are not far from having editors that will handle H.264 video in frame-accuracy for such tasks. Soon, you will not need an intermediary format, or even VirtualDub which is dependent on the VFW format. (But maybe you may have to remux to a container other than MKV, which would be lossless anyway).

When this type of software comes out, can it achieve lossless editing of Mpeg4/H.264 videos? (Even with the Long GOP compression)

[Cornucopia]

Assuming you had smart-rendering capability of whatever codec you were using (which is still in the future), you'd still have to render on frames where you:
1) Faded/Dissolved
2) Applied FX
3) Applied Color correction, or any kind of proc amp control
4) Mixed and matched Resolutions, Codecs/Containers & Framerates
5) Up/Down rezzed, Up/Down framerate converted
6) Applied Titles/Graphics
7) Adjusted frame positioning

Then, unless they are were I frame only, you'd be re-rendering anywhere from a 6-frame GOP to a ~300-frame GOP. THAT'S A LOT OF RENDERING.
And every rendering would reduce quality (because of recompression).

What's 90% of 90%? 81%
Then 72% 66% 59% 53% for further generations.
You're still lossy, even if your codec says you get to keep 90%!!!!

Best to use Uncompressed or Lossless or only slightly lossy Source codecs for source footage, use similar edit codecs for the editing process/workflow, and then and only then use very lossy distribution codecs for final playback. That's how they're meant to be used.

Scott

[PuzZLeR]

Okay I never knew mpeg4/H.264 encoding can cause such destruction to video files.

First I don't know if I made it clear but when I am talking about visually lossless, I mean to be able to edit and save without noticing the difference visually. (Maybe retaining 99% of quality visual wise). So I do not mean actual 100% lossless, but nevertheless 100% is better than 99%.

So basically from your post, there is no way to lossless edit a Mpeg4/H.264(DivXPlus,X2264,Xvid) video. (unless you use GOP length of 1). But what about future editors that will handle H.264 video in frame-accuracy as PuzZLeR talks about?

Not sure what you mean by "editing" but if it's only cuts, joins, and even fades, we are not far from having editors that will handle H.264 video in frame-accuracy for such tasks. Soon, you will not need an intermediary format, or even VirtualDub which is dependent on the VFW format. (But maybe you may have to remux to a container other than MKV, which would be lossless anyway).

When this type of software comes out, can it achieve lossless editing of Mpeg4/H.264 videos? (Even with the Long GOP compression)

Hi again,

Let me explain what I meant in case I upset anybody, although everybody here has been great.

As was mentioned to you, H.264, as well as other highly compressed formats like DivX, Xvid and WMV, etc, were never meant to be edit-friendly formats, only as a deliverable medium. Such was the sacrifice made to increase compression in their design as key frames are far apart.

However, so was MPEG-2. Today editing it with cuts and joins, even fades, is lossless. But don't misinterpret "lossless" 100% literally. There is a re-encoding necessary for MPEG-2 on such edits very near the few frames of the cuts/joins, and a recalculation of GOPs to perform the task, which is exactly what the MPEG editors I mentioned do BUT everything else in the stream is indeed completely lossless. And it's frame accurate too.

Now, using more recent versions of VirtualDub, and "smart rendering", even DivX/Xvid, which are formats more compressed than MPEG-2, are in the same type of editing situation today - completely lossless save for the frames near the cuts/joins/fades.

This is what I forsee soon with H.264 as VideoReDo is working on such an editor (currently still experimental). Of course, H.264 would need much more processing than most other formats for this, and may need more frames re-encoded near the cuts/joins, but it's doable.

However, I will repeat - it's always good practice to keep all Source. I believe the true video hardcores have multiple versions of their video - one as Source and the others as playback mediums encoded from the Source. Source is always retained separately. (Of course this figure could double with backups.)

I know it's more hard drive space to do this, but honestly this was fundamental to me in this hobby and changed it for the positive instead of forever agonizing about what format to convert it to in a lossy transcode.

[Cornucopia]

Correction to what you just said: FADES/Dissolves are NEVER smart-rendered/lossless - in ANY program. As a blending of 2 separate images (or an image with Black), they generate a NEW image that can/does include brightness values that weren't factored into the original quantization level. So, it's got to be re-rendered.

But, a bonus. For some formats that DON'T require a consistent GOP sequence, it's possible to have a cut that's on a I or P frame early in the ending GOP and it won't need to be re-rendered, just the arriving GOP (since that would lack it's normal I-frame). Smart, Smart Rendering.

Scott

[PuzZLeR]

Correction to what you just said: FADES/Dissolves are NEVER smart-rendered/lossless - in ANY program. As a blending of 2 separate images (or an image with Black), they generate a NEW image that can/does include brightness values that weren't factored into the original quantization level. So, it's got to be re-rendered.

I agree totally and I was assuming things.

My assumption was that such edits - fades, dissolves, alpha blends, etc, were for only a very short duration to smooth harsh cuts/joins. This is how they're mostly used.

These are offered in an MPEG dedicated NLE like Womble, and with VirtualDub for AVI formats and should be available for H.264 in the near future. They work like cuts/joins in that they leave the rest of the video intact quality-wise.

But I will iterate your point in that they are indeed lossy for their entire duration, and could be implemented over a long duration, which would make rendering these parts, including the entire timeline of the production if you could spread it that far, lossy.