How to Remove Visual Static (little white dots on dark background)

[mtepper27]

Is it possible to remove white dots from a .ts file?
[Attachment 44567 - Click to enlarge]

[mtepper27]

It may seem insignificant in the attached pic, but it's much worse in other videos.

[jagabo]

There are a few types of filters that can remove that sort of defect. Spacial and temporal noise reducers, dust/dirt removal filters, UnDot filters etc. A video sample would be much more useful. And some context. Is this a video capture? From a digital camcorder? Screen capture? Are they always in the same place? Move around randomly?

[mtepper27]

Thank you for the response. I've attached a 30 second video sample. This is a Hauppauge PVR video capture to my computer from a Directv Receiver. This specific Directv Receiver produces these white dots that move around randomly, while my other receivers do not do this.

[lordsmurf]

That's some sort of interference.

A median filter would also work. You have several filtering options.

But the ideal thing would be to find the interference, and remove the problem before recording into the video.

[mtepper27]

Absolutely agree with you about finding the problem. I called Directv earlier today and ordered a replacement receiver. But I have hundreds, if not thousands of sporting events recorded off that specific receiver. So now I must find a way to edit them with something other than VideoRedo. I am currently researching UnDot filters and it seems that AVISYNTH will be necessary to do any such editing.

[mtepper27]

Supported color formats:*YUY2,*YV12

SSE*/*MMX*compatible CPU


These are the requirements of undot. how can i determine if I meet the requirements.

[lordsmurf]

You can also try Median in VirtualDub.
However, Avisynth may be better to import then frameserve/export to avoid AVI lossless intermediary step.

This same error is common on homemade VHS tapes.

Your computer would have to be old as dirt to not have SSE*/MMX* ability.

[poisondeathray]

You mentioned thousands of sports content - If it's sports content, it will be 59.94, but the sample you uploaded is theatrical/film so that's actually 23.976 content in 59.94 (you have 3:2 duplicate pattern) . But I would leave it as 59.94 if it's mainly sports.

Undot or removegrain(1) is perfect for this, because it's the least damaging and will pickup every dot. removegrain(1) is the same as undot but slightly faster

Another option is ffmpeg , which has the removegrain filter ported from avisynth. This allows you to batch process very easily, including copying the audio stream into the container of your choice (I would choose mp4 or mkv), and if you have thousands to do, it's just much easier. You basically double click a batch file and it will process all the files in a folder. The output files can take on the same name as the input file and everything is automatic once you set up the batch

Test a few out first, convince yourself that's it's ok for your needs, and basically the only thing you need to decide on is the quality level and encoding settings . Most people would use x264 and maybe crf 16-20 for general use . Smaller crf values lead to larger filesizes and higher quality

Try out a few tests first , and if you like it someone will help you out with a batch. This is what it would look like for a single encode

ffmpeg -i "10 7 2017 NCAAFB Week 6 TCU vs West Virginia TEST PIECE.ts" -vf removegrain=1 -c:v libx264 -crf 16 -c:a copy test.mp4

(and I verified the output is the same as the avisynth version. Some ffmpeg filters do not work quite exactly like the avisynth version even though they are ported from avisynth; notable ones are IVTC filters)

[jagabo]

It looks like poisondeathray has it covered. If you want to use AviSynth you'll need a script like:

LWLibavVideoSource("10 7 2017 NCAAFB Week 6 TCU vs West Virginia TEST PIECE.ts") 
RemoveGrain(1)

[mtepper27]

Thank you all for your help. You've helped me save thousands of recordings. I am going to take some time to study ffmpeg and avisynth so I can better understand this stuff.

For future users with this problem, the simple and fast fix is the ffmpeg code line that poisondeathray posted. It doesn't even require video file conversion, but you can convert the file to mp4 or mkv if you'd like.

[jagabo]

Yes, the ffmpeg command is better suited for this simple task. You can also create a batch file to automate the process. You would use AviSynth if you needed more complex filtering.

[johnmeyer]

If the video is 23.976 that has been telecined to 29.97, then you need to return it to 23.976 using IVTC software before doing any enhancements. Most restoration software will not work well on video that contains those duplicate fields that are added when converting 23.976 material to 29.97.

[jagabo]

The OP mentioned "sporting events" so I would guess he doesn't have much 24 fps film based material. The sample clip (a commercial for a movie) was film with a little 60 fps video in the crawl at the bottom. The spots he's trying to fix change with very video frame.

[mtepper27]

What you do mean by "sporting events?" 95% of my stuff is sporting events. And all of my stuff is 59.94. I attached a commercial during a sporting event because the dots were most evident.

[jagabo]

Live sports are normally broadcast at 60 frames per second or 60 fields per second where every frame/field comes from a different point in time. 24 fps movies are also usually broadcast at 60 frames per second or 60 fields per second -- but there are only 24 different pictures every second (aside from compression artifacts, video noise, etc.). Film frames are repeated 2 or 3 times to create 60 video frames, alternating between the two (24 * 2.5 = 60). So for movies (and most TV series) you can remove all the duplicates and encode at 24 fps to get better results. That's what johnmeyer was referring to. I was pointing out that you said you had "sporting events" so I speculated most of what you are dealing with is live sports, not suitable for 24 fps.

[johnmeyer]

+1 jagabo.