1. Which version(s) of VPX?

2. Does it do AVCHD, both interlaced and progressive?

3. Can you switch it on and off? Do I have to do something that I have not mentioned?

4. Do you get any indication of when it is copying unaltered GOPs and rendering altered GOPs?

5. Do you use 24, 50 or 60 frames/fields per second source?

6. Why do you think that I saw no evidence of it?

7. Do you have any comments on my testing?

@peter-duke

1. Which version(s) of VPX?

Smart copy = Smart render - the name changed. All versions of VPX from 4 onwards have and do support Smart render / Smart copy.

2. Does it do AVCHD, both interlaced and progressive?

Technically it can and is part of the specification, however it is Interleave only in VPX using the Intel HD codecs, you have to use the Main Concept codec to be able to select Progressive, however another issue may arise using Hardware Acceleration - you may get a black video.

3. Can you switch it on and off? Do I have to do something that I have not mentioned?

Yes as you have found.

4. Do you get any indication of when it is copying unaltered GOPs and rendering altered GOPs?

Yes you may see the words Smart copy in the export progress dialog when it is being used.

5. Do you use 24, 50 or 60 frames/fields per second source?

In my case all my video is 25 fps interleaved, I have used 30 fps progressive from one of my sportscams however mixing framerates can cause issues with judder in pans.

. . . . AVCHD (MPEG4) . . .

AVCHD is not MP4, they are different container file formats, they both may contain, for example, h.264 or AVC codec encoded video, however the AVCHD is more heavily compressed than MP4 while retaining or having better quality, for the same bitrates the AVCHD file should be smaller than the equivalent MP4 file.

HTH

John EB

Smart Copy is not Smart Render. See the manual. (In the VPX8 manual it is on page 369 for MPEG-1/2 and on page 375 for MPEG-4 H.264.) and see my interpretation of it in my first post.

Smart Copy is apparently intended only for simple cuts at the beginning and/or end of an otherwise unaltered video clip. The actual cut point at the start will be adjusted later if necessary so that the cut occurs on an I-frame, and at the end it will be adjusted back if necessary to the nearest I-frame.

I tried to Smart Copy a clip which had a short subtitle inserted partway along the clip. It re-rendered the whole clip!

Yes, I am aware that AVCHD is not MP4. They both may use MPEG-4 part 10 (H.264) video encoding, which I am interested, in but AVCHD uses a modified MPEG-2 transport stream container, as used in Blu-ray discs, while MP4 uses a MPEG-4 part 14 container.

You say that Smart Render disappeared at VPX4 and later, but you must mean VPX5 at least, because VPX4 which I have does have Smart Render, but I found that it had a bug (an artifact introduced near a cut).

In that case it would appear that VPX8 which I have and presumably VPX9 which is now out only do Smart Copy and not Smart Render. That is too restrictive for me, so I will soldier on looking for the Holy Grail. Cyberlink PowerDirector is the best smart rendering video editor that I know of so far, with Corel Video Studio coming in second. However, I still have to run outputs from both editors through TMPEGEnc Smart Renderer to clean them up to improve compatibility with other software. Cyberlink PD requires less cleanup than Corel VS.

Since the VPX8 manual still mentions Smart Render (and Smart Encoding at one point) it ought to be updated to delete reference to it.

Hi

. . . . Smart Copy is not Smart Render . . . my interpretation . . . .

A question of interpretation, my interpretation is that they are same (one being a sub set of the other) with different scopes of usage depending on the degree of re-encoding needed and which codec used for encoding.

To be specific, using the Intel HD codec (Default) the only option is Smart copy, using the MainConcept codec the option is Smart Render with Smart copy as a sub option.

However as I said in point 2 above about the MainConcept codec - another issue may arise using Hardware Acceleration - you may get a black video.

Another issue I did not mention previously with the MainConcept codec occurs on an Intel only PC ie when using the integrated GPU on the processor for rendering, is the possibility of getting a zero byte (empty) file .

. . . . You say that Smart Render disappeared at VPX4 and later, but you must mean VPX5 at least . . .

Nope, never mentioned it disappearing.

. . . . I still have to run outputs from both editors through TMPEGEnc Smart Renderer to clean them up to improve compatibility with other software. . . . .

Are you converting to h.265 ?

John EB

If Smart Copy is a subset of Smart Render then they are not always the same, but I do not wish to dwell on semantics. What I want is when I render a project that has a mixture of unaltered and altered GOPs due to editing, only the altered GOPs are re-encoded. In my experience, Smart Copy does not do that.

I don't use hardware acceleration, so we don't need to consider that here.

I am not converting to H.265. I am using AVCHD which uses video encoded to H.264 aka MPEG-4 AVC aka MPEG-4 part 10, and I wish to keep it that way or I will certainly not be able to smart render.

You say that the Intel codec only gives Smart Copy option but that the Main Concept coder gives both Smart Render and Smart Copy options. How do you select the Codec?

The manual implies that MPEG-1/2 is encoded by Main Concept so I suppose that MPEG-4 (whether AVC or not) is encoded by Intel, and if so then I am stymied.

OK, the plot thickens. On looking through the manual I saw reference to paying for the MainConcept MPEG-4 codec. I was not aware that this was an option that one must explicitly ask for. Well I paid my few dollars and installed it. This codec must then be selected in Program Settings. Now the advanced button on the render dialog opens to a different window which allows me to select Smart Render, and if that is set, Smart Copy.

I have played with it a bit but Smart Render seems to behave just like Smart Copy!

I placed a short subtitle part way along a clip and the whole clip was re-rendered. I cut the main clip either side of the subtitle so that only the middle subclip had the subtitle. If I click on the Smart Render info button, it tells me that the first and last portions will be smart rendered and the middle will be rendered. You beauty! 😄 But no, the whole lot is rendered again! 😬

I will keep testing...

I loaded an AVCHD clip with stereo AC3 audio into Magix Video Pro X and with no editing whatsoever, I selected to export it as AVCHD, with the same same settings, using the MainConcept H.264 codec. I selected Smart Render in the Advanced settings.

On clicking "Smart render info..." a box came up saying, "The current disc project contains audio in Dolby Digital format. The sound will be encoded again with the current settings. To keep the original sound, please click on "Copy mode".

If I click on "Copy mode", The clip is processed exactly the same as if I had selected "Smart Copy" instead of "Smart Render". All but the last 13 frames are copied exactly, and the final 13 frames are missing,  (The GOP size is 13.)

If instead I click on "Continue", the whole clip is re-rendered and takes about twice real time, the same as if I had not selected to smart render.

Since it complained about the AC3 audio, which is standard in AVCHD, I converted the audio to uncompressed wav format and remuxed the video. This time there was no complaint about the audio, but I got a complaint that the file was incompatible.

I have carried out other tests with some other anomalies, but at no time was I able to smart render, i.e. copy all unaltered video GOPs without recoding.

Has anybody successfully smart rendered AVCHD? If so, what version of MVPX and how did you confirm that it had not been re-rendered? Any comments why I have been unsuccessful?

Hi

Yes - see below

No edits

Cuts only

1 cut + 1 xfade

Notes:

1. the MainConcept codec was used for exports with Smart render and Smart copy selected.
    
2. export settings for resolution and framerate same as source video, bitrate settings to default - however see 3 & 4
    
3. the source files are AVCHD 5.1 Surround Sound 5.1, Surround Sound 5.1 was activated in the Mixer - if the export is set to stereo then Smart render / Smart copy does not occur.
    
4. export Interlace setting was set to match source video - TFF for the above - otherwise re-encoding occurs
    
5. No hardware acceleration was available MC codec does not work correctly with Intel integrated GPU

For some reason the last clip encode status is not recorded !

HTH

John EB

Thanks for your reply.

Yes, I am able to smart copy, but that discards a wanted part at the end of my video, and does not work if a subtitle or crossfade is added to a portion of the clip. I don't want to smart copy; I want to smart render.

In your last example with a crossfade, you have chosen to smart render, it says that it will smart render but then to the right it says that it was unable to smart render.

Hi

. . . . In your last example with a crossfade, you have chosen to smart render, it says that it will smart render but then to the right it says that it was unable to smart render. . . . .

The options for Smart render and Smart copy were the same for all 3 tests - ie both selected. The program decided which it would use.

In tests 1 and 2 the program did exactly what the manuals says it would do - with no edits, or cuts only, it Smart copies.

However, in test 3, the first clip should have been Smart copied, it was unchanged from test 2, however the program decided to Smart render it.

The second clip was also Smart rendered up to the start of the crossfade, the program then switched to Render as planned, because a fade in or out, a crossfade or any section that involves 2 video, image or title objects, or pans, zooms etc. must be fully re-rendered.

I think the sentence where it describes what Smart render can do is incomplete - I think it should say something like this:

'Smart Render lowers the demand on the encoder for AVCHD material. In the production of AVCHD files, only those parts of the movie that were changed in the program (e.g. by video cleaning or effects). Fades, transitions, movement/zoom effects, etc will be re-encoded '.

Why the remainder of the third clip was also rendered I do not know.

John EB

John

What happens when you place one clip on the timeline with no edits and then Smart Render (not Copy)?

Does MVPX report that it is planning to smart render the clip but executed a normal render, with a message that smart render could not be started?

With two or more clips does it say that all except the last clip were smart rendered, that the last clip was rendered and smart render could not be started?

Depending on the speed of your computer I expect that normal render would take longer than real time (about twice on mine) and smart render to take much less (about one quarter on mine).

Do render times suggest smart or normal rendering?

Note:

I have Sony (now Magix) Vegas Pro and am able to do detailed comparisons of pairs of videos to see if frames are truly identical or not. For an A-B direct visual comparison I see that the rendered video has a very slight brownish cast, and the contrast is very slightly reduced. The histogram shows that the highs have been clipped to broadcast levels (255 -> 235), which is no use to me since I do not intend my work to be broadcast.

Hi

. . . . What happens when you place one clip on the timeline with no edits and then Smart Render (not Copy)? . . . .

The clip gets rendered.

. . . . Does MVPX report that it is planning to smart render the clip but executed a normal render, with a message that smart render could not be started? . . . .

So far I have had this occur once in initial testing.

. . . . all except the last clip were smart rendered . . . .

Correct, if you click the indicated button shown below you get the intended action list - however there is an issue see images below

Result:

. . . . I expect that normal render would take longer than real time (about twice on mine) and smart render to take much less (about one quarter on mine) . . . .

I get the following times (no hardware acceleration) for the above 1m 37s timeline no effects applied

Main Concept codec:

Smart render - 1m 44 sec *

Full render - 1m 30 sec

and for completeness

Smart copy - 10 sec **

Intel HD codec (default) no hardware acceleration

Smart copy - 7 sec **

Full render - 2m 35 sec

Intel HD codec (default) with hardware acceleration

Full render - 49 sec

Note:

* Why the Smart render would take longer than a full render is anyones guess!

** I suspect the difference in time is due to the MC codec taking about 3 secs to load and start.

The Vegas Pro issue is probably due to IRE being selected - however this topic should be in the Vegas forum which is over here

HTH

John EB

Can someone comment on the advantage of using Smart Render, Smart Copy. Why would you use it, what does the main concept buy us.

Hi George

A good question which is going to get a lot of opinions on both sides.

. . . . the advantage of using Smart Render, Smart Copy . . . .

I never used this in any exporting of projects since starting with MEP 11 way back before Intel developed the i series processors with integrated GPU and a graphics card was needed and the MC codec was the defacto standard.

I cannot think of a project I have done where this would even have kicked in, they involve effects, transitions - cut, crossfade and the occasional wipe, collages, etc that make Smart render / Smart copy not possible.

So, in my case, no advantage at all.

. . . . .what does the main concept buy us . . . .

In my case slower rendering, cannot be used with Hardware Acceleration and lower quality compared to the Intel HD codec. This is on an Intel PC with no AMD or NVidia graphics card.

John EB

If smart render worked properly, then it would have the advantages of fast renders and minimal loss of quality, but it must be very difficult to implement reliably in video that uses interframe compression such as the various flavours of MPEG. It cannot be applied to frames that have been altered in any way, of course, but neither can it be applied to B and P frames that rely on these frames through bothway (B) and forward prediction (P).

I have only heard of Smart copy here, and has the advantage of relative simplicity, because it is apparently restricted to video with simple cuts only, and incurs truncation back to the nearest I frames, which do not rely on prediction from other frames.

So far as the MainConcept H.264 codec is concerned, I have yet to see any use for it, since I have been unable to get it to smart render, and we can smart copy with the default codec.

My videos are relatively simple with minimal effects. I use subtitles as comments here and there, colour correction for clips shot through tinted vehicle windows, lifted shadows for back-lit scenes and sometimes anti-shake. I usually have to trim the end of clips to remove camera movement because it did not stop recording immediately. Other than that, the video is largely unchanged and I have found smart rendering worthwhile. For interlaced AVCHD I have been using Vegas Pro 9c, which doesn't always smart render when it should, which is presumably why later versions of Vegas do not have it. I am now using progressive AVCHD, which is not smart rendered by any version of Vegas, hence my search for another video editor. The best I have found so far is Cyberlink PowerDirector, with the output cleaned up with TMPGEnc Smart Renderer for better compatibility, but unfortunately PowerDirector lacks the flexibility that I have become use to in a video editor.

Johnebaker, it's Greg, G-R-E-G.

Anyway, I have a system update that has not been posted in my profile. I got tired of the problems with my old PC, and with the help of someone here, half way around the world, I built another system to help with the editing. It should be the start of a new thread, but I'll let it out here. Amazing build, I never did it before, now I am sure glad I did it. SuperFast!. Rendering is amazing. Editing a breeze. Same Magix problems tho. What little I know about Main Concept, seems like a gimmick. Flickering between transitions with effects still the worst. Title flicker too. Same stuff, you have to forget about effects,or learn a way around it. You have to get it right in the camera, effects for corrections will kill the process.

For example, a single track of 34 different Panasonic 1920X1080 60p MTS clips, 16 minutes long, on one timeline, with transitions between each, renders HDTV 1920x1080 H264 59.94FPS in about 12 minutes.

Here is what I built:

Corsair 750D case

Intel i7 8700K Coffee Lake micro processor

Asus Maximus X Hero Wi-Fi AC MB

Corsair RMX750 FM 80+G ATX Power Supply

Win 10 PRO 64BIT

Corsair Hydro H115I Pro cooler

ASUS 24X DVDRW SATA

Corsair 32GB 2x16 D4 2666 VGN C16 RAM

Samsung E 500GB 860 EVO 2.5SATA3 SSD for C:

2) Samsung E 250GB 960 EVO NVME M.2 SSD on MB

Seagate Barracuda Pro 4TB HD

Klipsch Pro Media surround sound (existing)

(no graphics card, I stopped using my Nvidia Quadro K2200).

I wish Magix tech support would read these forums, and get a hint of the problems we are experiencing, they fall short of being a true leader in the video editing business because of their lack of attention to the issues we post here.

@gmlotkow

My apologies Greg.

John EB

Thanks johnebaker, i read what i could understand, i think the only thing i can gather is that i need to pay for the Mpeg 4 codec then i can take it further ?