Technical Questions Thread (Collective Brain Moochathon 2K24) ???

We're all good at different stuff - our ranks contain programmers, artists, musicians, AV nerds and people from many other technical backgrounds and I thought it might be nice to have a thread where we can ask guilt-free technical questions and mooch off the collective IC brainbox.


I'll go first! I posted this in the streaming thread, but with no success there I'm bringing my question here.

I need to be able to record 1080p 50fps 50Hz (specifically 50Hz and without conversion to 60Hz) footage from a HDMI device for something I’m working on. Ideally I should be able to schedule recordings as I may not be present when the feed needs to be recorded. The device I’d be recording does use HDCP, but I already have a HDBaseT matrix that _should_ strip it off so that’s not an issue for me.

What solutions, stand-alone or computer-based, exist?

[“Technical Questions Thread”,“Technical Questions Thread (Collective Brain Moochathon 2K22) \ud83e\udde0\ud83e\udde0\ud83e\udde0”]

(apologies billy, I have nothing to offer to help your query above. The only thing that came to mind is that maybe vMix can do it, but that won't help with the scheduling aspect and obviously there is a cost involved)


@“captain”#p64460 rejj by the way, how did you manage to extract The Fork Video from the bowels of the net? I would like to educate myself/get current on the latest tips & tricks of web navigation. I kneel before you, seeking wisdom

I figured this may be better suited over in this thread.

First, a search for the exact headline text from your screenshot showed that, amazingly, the page itself is somehow still up:
[upl-image-preview url=//]
Trying to click the fork article itself wasn't so helpful, however:
[upl-image-preview url=//]

I headed over to the wayback machine, and found the earliest scrape for the page instead:
This then linked to the scraped version of the fork article, which I then also went back to the earliest revision of:
On that page I hit the "watch bigger" link to make sure I was finding the largest resolution they had available.

This is the page that _would_ have had the flash player in it, but it just looks rather empty now. Right click on something near where the player was supposed to be (I chose the headline) and opening the browser dev tools via "Inspect Element" exposes the structure of the current page (called the DOM, the "Document Object Model") and I can see where the player would normally be
[upl-image-preview url=//]
Expanding the `<div id="vid_player">` node reveals:
[upl-image-preview url=//]
which shows us the URL where the flash player itself used to live (the `IGNPlayer.swf`) but also shows that the flash player was loading a config file.
Hoping it was still there, I opened a new tab and pasted in []( and luckily that config file still exists. Reformatting it to make it easier to read revealed the following right near the top of the file:

``` "playlist": { "media": { "url": "", ```

... and that url, [](, is the one pointing to the mp4 file that luckily for us is still there.

(sorry billy, I wish I could help)

@"rejj"#p64485 Thank you!!! In my own investigation I did try inspecting the page following my flash emulator efforts, but I could not at all parse the lines of gobbledegook it proceeded to show me; nor would I have known what to do with that config file had I found it. Armed with your knowledge I may next time persevere.

This is good hacker info.


When you make something like this, do you merge all the tracks in a DAW or Audacity or what? Or is it all in a video editor (presumably where the track names/text editing come in as well)?

@“captain”#p64583 I think for the Suikoden II one I used Garageband, but I would really not recommend it for this type of project because it has no function for applying “fade outs” to the individual audio clips you are knitting together. Instead you have to use the volume automation functionality for the entire track, which is tied to the timeline instead of the audio clip, so if you apply a volume fade at a certain point and then move one of your audio clips, the fadeout happens in the wrong place…basically what I'm saying is use audacity or anything else that allows you to fade audio clips directly

for the video aspect i painstakingly made separate images for each track in MacOS' Preview program, then dropped them into iMovie and synced them with the tracks. i did this instead of adding the titles in iMovie because i did not like any of iMovie's title or font options (all look like dad's vacation slideshow) and i have no other video editing program

i actually have the audio for a Suikoden I Merry Medley ready to go but have not finished the video yet because i dread making all of the titles again......


lol even more of a champion in light of the lengths you went to to put that together. I asked the question specifically thinking "I could add titles in Preview and string them together like a slideshow... but tapevulture probably has a shortcut." Gonna see if Windows' bare bones "Video Editor" app fares any better.

~(~(~(~(gotta get a cracked version of Premiere or something one of these days))))


"Shotcut" is a good, free barebones video editing program if you want a step above the windows video editor

@“captain”#p64633 i think the ultimate way would be to write some kind of script that pulls the song titles and automatically generates the images. i just checked and Preview doesn't work with Applescript…not sure what other kind of image-editing software is available for Mac that would also work with Applescript

I am pretty desirous of just being able to crank these out so would really like to find a better way to do it. i made the suikoden I medley in ableton and i think it's possible to add images to tracks and export a video so may try that

let me know if you come up with anything


@"billy "#p64384 I need to be able to record 1080p 50fps 50Hz

i'm also no help, but i'm curious what the difference between fps and hz is. i've always used per second and hertz interchangeably.


Hz is the number of times the screen refreshes in one second and is normally fixed, unless you have a fancy VRR (variable refresh rate) display. On most TVs this figure is 60Hz, although TVs in PAL-land used to exclusively run at 50Hz and now switch between the two depending on the source. Many TVs can also drop down to 24Hz (or cheat by running at 48Hz) for Blu-ray discs.

FPS is the number of unique frames in the video per second. To ensure smooth motion without uneven judder, this should be the same as or divisible by the refresh rate (Hz) of the feed.

In a nutshell, you could be playing a game that runs at 30fps, but your TV is actually refreshing at 60Hz.


@"billy "#p64687 In a nutshell, you could be playing a game that runs at 30fps, but your TV is actually refreshing at 60Hz

apologies if i'm being dumb, but the only way i can think that the refresh rate of the display relates to the video captured is if you're trying to do something like pointing a camera at a tv. is that right?

@“pasquinelli”#p64712 not quite, the video feed has to match the display. So, like, I’m playing a game that runs at 30fps (or 60fps or 43fps or 12fps) which my console nonetheless outputs as a 60Hz video signal to my 60Hz TV.

Frame rate (fps) is just for visual smoothness, the actual refresh rate of the video signal and display are what need to match up on a technical level. The ideal is of course that both numbers are the same, so in my example I’d be recording a 50Hz video feed that happens to contain one frame for each screen refresh, therefore giving maximum smoothness and motion clarity.

Put another way, a 50fps source video recorded at 60Hz would look juddery and bad, as there are extra screen refreshes that would need to be filled with blank or duplicate frames to fill one second. Record it at 50Hz however, and the screen refresh perfectly matches the number of actual video frames.

@"billy "#p64720 i understand you want to record at the frame rate of the source video signal. faster and your recording has extra frames, slower and your recording drops frames. what i don't understand is where the refresh rate of the display comes in.

@“pasquinelli”#p64725 in my case, the recording would be coming from a 50Hz device, so I’d need to ensure that my capture device could receive this signal and record the 50Hz, 50fps signal without converting it to 60Hz.


@"billy "#p64720 the actual refresh rate of the video signal and display are what need to match up on a technical level.

so maybe here's the kernal of my confusion. a video signal, to my understanding, doesn't have a refresh rate, it has a frame rate. refresh rate is specifically the rate at which the pixels on a screen need to be stimulated to maintain their state. in an old crt for instance, refresh rate was the number of times the phosphores were charged to keep them glowing.

@"billy "#p64727 have you seen this thread? the first response mentions two brands of capture cards that support any combination of resolution and frame rate that is within their data limit. i looked into one, datapath, and they are pricey.

@“pasquinelli”#p64729 Video signals have refresh rates for sure. A new frame is sent every 1/50 of a second. Even if the visual information is the same.

On a CRT for example, the video signal is directly telling the electron gun how fast to move and which phosphors to illuminate in real time. The signal has a vertical sync pulse that tells the gun when to reset back to the top. The rate of vertical sync pulses is the vertical refresh rate (e.g. 50hz). Even a still image will be sent 50 times per second.


@“Kez”#p64742 Video signals have refresh rates for sure. A new frame is sent every 1/50 of a second. Even if the visual information is the same.

can a video's frame rate differ from its refresh rate?

@“pasquinelli”#p64750 Well, I would say a video has a frame rate and a video signal has a refresh rate. For another example, most PC monitors run at 60hz. That is their refresh rate, a computer connected to that monitor will know to send an image every 1/60 of a second. If I watch YouTube or Netflix on my PC, that is likely to be a 24fps video. But my monitor is still running at 60hz, meaning the PC updates the monitor every 1/60 of a second - even if the video has not yet updated. 24 does not divide into 60, so you end up with uneven frame pacing. Here's a representation of that from Rtings:


Although the video is at 24fps, the display expects a 60hz signal, so the video signal itself is 60hz. If you looked at it on an oscilloscope for example, you would be able to discern that it was a 60hz signal (but it would be more difficult to tell it was 24fps).