Best GoPro Resolution to make DVD and BluRay

[BaruceBR]

I've been filming motorcycle trips on GoPros for more than 10 years. Have always used GoPro resolution setting at 1080, which after 'editing' with Pinnacle or Video Studio, produced wonderful quality DVDs. Last year I got a BluRay player and a BluRay burner... so on last year's trip, I recorded with the next step up (from 1080) at 2.7K, and that yielded really great BluRay results. But when I output the same video project to DVD, video quality is poor... lots of what I might call artifacts in scenes that involved movement (most of them). So looking for suggestions on best GoPro resolution settings to yield high quality results for BOTH BluRay and DVD... or how to process the 2.7k (mp4s) for best results on both platforms. Thanks.

[Skiller]

Should not make basically any difference at all when going for DVD. But because you say it does for you, it means there is a problem somewhere along the line (it's not related to your GoPro's settings). But without more details, I can't say anything more specific.

What settings are you using in your video editing software and what do the "artifacts in scenes that involve movement" look like?

[Cornucopia]

My guess is that the 1080 setting was an easy multiple of the framerate, so makes for natural movement on the dvd, but the 2.7k doesn't have the same framerate options and so what is left is not a simple multiple for the dvd, though it may be for the bd.

For example, 1080p60 --> 480i60 is easy but 2.7kP24 --> 480i60 will have judder even when professionally telecined.

Scott

[BaruceBR]

The MP4s from the GoPro were all shot at 30fps, 2.7K, 16:9. Loaded into Video Studio and then Output to Blu-Ray disk with default settings of 1440x1080, 29.97fps, 16:9, while output to DVD settings are 720x480, 29.97fps, 16:9. Blu-Ray looks great, but on the DVDs, things like power lines, highway stripes, and horizontal lines particularly appear to be 'striped and moving' on playback... which is very visually distracting. I don't know what settings I could change for DVD output to correct the problem... maybe I need to talk to the Corel Video Studio folks?

[jagabo]

on the DVDs, things like power lines, highway stripes, and horizontal lines particularly appear to be 'striped and moving' on playback...

Of course. That's what happens if you downscale too sharply. And you're probably encoding interlaced making the problem worse. Use a less sharp downscaling filter and an interlace de-flicker filter before encoding.

[Skiller]

We've had this just a few days ago – interlaced video requires a vertical low-pass to look alright on any display device. It's easily forgotten when a resize from HD down to SD occurs.

As jagabo mentions, in your video editing software look for something called "de-flicker filter" or similar.


Reading material regarding this matter: Kell Factor (why) and Interline twitter (what the artifact looks like)

[BaruceBR]

Thanks for those suggestions and that info... I'll check that out...

[TreeTops]

Skiller- GoPro doesn't shoot interlaced video.

[Skiller]

Skiller- GoPro doesn't shoot interlaced video.

So? But the resulting DVD might be.

[Bwaak]

The MP4s from the GoPro were all shot at 30fps, 2.7K, 16:9.

I assume that by using GoPro you shoot a lot of motion. Why would you shoot at 30 fps is beyond me.

Loaded into Video Studio and then Output to Blu-Ray disk with default settings of 1440x1080, 29.97fps, 16:9

Do you prefer 1440x1080 to 1920x1080 or just want to save on bitrate?

while output to DVD settings are 720x480, 29.97fps, 16:9. Blu-Ray looks great, but on the DVDs, things like power lines, highway stripes, and horizontal lines particularly appear to be 'striped and moving' on playback... which is very visually distracting. I don't know what settings I could change for DVD output to correct the problem... maybe I need to talk to the Corel Video Studio folks?

Check the setting for DVD authoring, is there a way to declare the output as progressive scan. DVD-video is a format that is interlaced at its core, but with a combination of flags it can carry progressive content with whatever image cadence you need. Better authoring tools can author progressive-scan DVD, and better TV sets can correctly play them.

Another option is to shoot at 60 fps, then blur vertically, downscale, and author as regular interlaced DVD, this would ensure full 60 images per second motion.

These links seem relevant:
https://forum.blackmagicdesign.com/viewtopic.php?f=21&t=151891
https://www.vegascreativesoftware.info/us/forum/interlaced-hd-to-dvd-again-some-test-renders--84017/

[Skiller]

During playback, depending on the combination of hardware and connections used, there is a good chance the progressive flags do nothing at all to aid the problem of violating Kell Factor because the video may be assumed to be interlaced later, outside the playback hardware, thus interline twitter still occurs.

Here is the only solution that always works and every well made DVD sticks to it: DVDs need to be vertically low-passed. Always. Even for progressive content.

[jagabo]

Here are a pair of videos. They are encoded as interlaced AVC but the issue is the same with interlaced MPEG 2 (DVD). One is sharp, the other is vertically low pass filtered (blurred vertically) before being interlaced. The sharp video will look much worse on most players/displays.

<edit>
I just realized the videos I uploaded here were messed up. I've deleted them for the time being.
</edit>


</edit2>
I've corrected the videos. There is much less difference between the two now. But I've seen much worse with other videos. Note that the type of deinterlacing will effect the quality too.
</edit2>

[Bwaak]

The script by NickHope from the Vegas forum. The forum would not navigate to pages other than the first, but luckily the script is on the first page. I am posting it here for discussion and posterity (I may use it myself), maybe there is an improved version on other pages, which are not accessible to me. @jagabo, can you comment or post your own script, please.

Obviously, no need for AssumeTTF and TDeint for GoPro footage.

In particular, is it correct to expand video levels to computer levels in assumption that "Frameserver converts from RGB to YUY2" ? Did he mean frameserver that he used with Vegas? This is probably not true for other use cases?

# High quality HD to SD conversion script. It is slow.
# Retains detail but reduces artefacts such as line twitter on CRT displays.

# Set maximum memory.
# Setting M:
# - First try without the SetMemoryMax line
# - However, using the SetMemoryMax line and a good value for
# M might allow more threads and so give more speed.
# Particularly important for slower QTGMC settings
# - Try values 400,600,800,1000 etc.
# SetMemoryMax(M)

# Set multi-threaded mode.
# Setting X:
# - Start at the number of cores in your machine.
# - If it crashes, decrease 1 at a time.
# - Otherwise increase 1 at a time until CPU usage is very,
# very close to 100%, don't go too far or it will slow down.

SetMTMode(5, X)

# Open frameserved source. Frameserve in YUY2.
# Change path and file name as appropriate.

AviSource("d:\fs.avi")

# Expand levels from [16,235] to [0,255]
# Otherwise DVD will have insufficient contrast.
# Counteracts levels squeeze when Frameserver converted from RGB to YUY2.
# Omit out if you conformed levels to full range in your NLE

ColorYUV(levels="TV->PC")

# Assume footage is top field first.
# If it's bottom field first then use AssumeBFF.

AssumeTFF

# Set multi-threaded mode.

SetMTMode(2)

# Bob with bi-directionally, motion adaptive, sharp deinterlacer.
# Produces double-rate, progressive, full height output.

TDeint(mode=1)

# -----
# Here one could save a lossless intermediate
# (e.g. YUY2 Lagarith avi in VirtualDub)
# Then do the remainder in a separate script.
# -----

# Resize to double NTSC

bicubicresize(1440,960)

# Reduce width with sharpening

bicubicresize(720,960,-0.8,0.6)

# Reduce height with sharpening

bicubicresize(720,480,-0.8,0.6)

# Temporally smooth / remove horizontal shimmering
# Setting Y:
# - Start at about half number of cores and tweak upwards
# or downwards for best speed. Y=1 often works well.
# - Balance this setting with X (i.e. if you increase X,
# you might need to decrease Y and vice versa).

QTGMC(TR0=1,TR1=1,TR2=2,InputType=1,EdiThreads=Y)

# Reduce line twitter on interlaced displays

blur(0.0,1.0) # vertical blur
sharpen(0.0,0.75) # vertical sharpen

# Replace the above 2 lines with the following 4 lines
# for more low-pass filtering
# blur(0.0,1.0) # vertical blur
# sharpen(0.0,0.51) # vertical sharpen
# blur(0.0,1.0) # vertical blur
# sharpen(0.0,0.85) # vertical sharpen

# Re-interlace:

assumetff()
separatefields()
SelectEvery(4,0,3)
Weave()

# This line may or may not be necessary.
# Try removing it and see if you get more speed.

Distributor()

[Skiller]

I think the levels issue might be related to "studio" RGB levels in Vegas. Vegas works in RGB but it can do both studio RGB (16-235) and normal RGB (0-255). I can't see any other reason why this would be necessary.


Thoughts on the script:

• TDeint is worse than Yadif or Yadifmod and not that fast either, wouldn't use.

• Doing the resize this way gives an artificial sharpness and contouring, similar to native SD content. Matter of taste.

• QTGMC call seems superflous to me. Don't see what's that supposed to fix other than TDeint artifacts.

• Vertical low-pass is quite aggressive. Remember, even native SD is of course not entirely free of shimmering (interline twitter) and trying to completely get rid of it only nukes the vertical detail to the point where there is no benefit left in using 576i over 288p (of course 288p is no option for DVD, unless you want to use VCD resolution).

My standard call for this, which for me turned out to be the correct balance in almost all cases:

Blur(0, 0.7).Sharpen(0, 0.4)

It doesn't need more than that. If anything, for a soft source the Blur call can be reduced to Blur(0, 0.6).

[Bwaak]

Thanks, @Skiller. I am not sure when to blur: before resizing or after, or maybe before and after? Because, suppose, there is a thin horizontal line, if I resize it like this, it may either disappear completely, or appear only in some frames, which will cause flicker similar to interline twitter. If I blur it before downscaling, it will lose contrast and will be wider, so when scaled down it will likely remain in all the frames. OTOH, scaling introduces artefacts, which should be dealt with by blurring. Um... so, before AND after? Unless the resizers are smart enough to preserve thin lines.

[Skiller]

Because, suppose, there is a thin horizontal line, if I resize it like this, it may either disappear completely, or appear only in some frames, which will cause flicker

This only happens with very simple resize algorithms (such a bilinear and point) which one should not use for this anyways. Bicubic at default (b, c parameters) or close to default is fine, personally I like Spline16 best as it's very precise and neutral but not blurry or artificially sharp. A 1px horizontal line won't disappear and reappear in some frames when resizing from 1080 to 576 with these.


Therefore...

I am not sure when to blur: before resizing or after

... after resizing, only once.

[jagabo]

AviSynth's BilinearResize() will not lose thin lines the way a PointResize() would. Simple interpolation only bilinear filters (like VirtualDub's) will lose thin lines.

I did a simple Blur(0.0, 1.0) in the video I posted earlier. A smarter deflicker would limit the blurring to only the highest contrast edges. Something like this:

# DVD sized frame
blurred = Blur(0.0, 1.0)
emask = mt_lutxy(last, blurred, "x y - abs", chroma="-128").ColorYUV(gain_y=4000, off_y=-120).mt_expand().Blur(1.4)
Overlay(last, blurred, mask=emask)

[BaruceBR]

I tried shooting at 60fps... but results didn't turn out well... and thought it was because Blu-Ray and DVD output options are only 30fps (29.97) in both Pinnacle Studio and Visual Studio, although it could be a downsizing problem... I wasn't sure... so started shooting at only 30fps...

[jagabo]

If you intend to make DVDs and you want smooth motion you should shoot at 59.94 fps. DVD is 29.97 frames per second but when interlaced you get 59.94 motion increments per second. That's because interlaced frames contain two separate half-resolution images, intended to be displayed separately and sequentially.

[BaruceBR]

I will try to get out and shoot some additional 'test' footage with 30 and 60 fps and then run thru Video Studio to compare the results... both at 1080 and 2.7k. Thanks for the suggestions and info.

[jagabo]

Download 24v30v60.avi from this post:

https://forum.videohelp.com/threads/307004-Best-framerate-conversion-%28eg-23-97-to-30...29#post1888926

See the difference between 24p, 30p and 60p on a 60p display (assuming your computer monitor is running at 60p).

[4kblurayguru]

Reshoot in 60fps or use 1/60 shutter
use 720p if 1080p doesn't allow 60fps

use separate software for everything, editing, encoding, authoring, burning.
all in one solutions always lack something.

DVD is 60i because NTSC is 60i
Hollywood movies are encoded as 24fps but add interlace pull down flags so it would show 60i on CRT but show progressive (24fps) on HDTV.
video must be encoded as 60i

try to avoid recording 30fps, I refer to it as internet frame rate .

HD/UHD TV fixed the NTSC problem.

watch this video
https://invidious.fdn.fr/watch?v=B0ndYWlMkXI