5 ms·

It's funny how often these videos are from a camera pointed at a monitor, instead of a direct digital copy. I assume extracting the actual file is logistically

It's funny how often these videos are from a camera pointed at a monitor, instead of a direct digital copy. I assume extracting the actual file is logistically tricky due to both technical and bureaucratic reasons.

denysvitali 2y ago
This assumes that it's available in digital form. Knowing Japan, there is a chance this is an analog CCTV
- Wowfunhappy 2y ago
  Surely it would still be cleaner to digitize the tape (?) than to point a camera at the screen, wouldn't it?
  - pistoleer 2y ago
    This was faster
accrual 2y ago
Yeah, similar for interesting events caught on security cameras. I assume these videos tend to come from the operator who only has access to view but not to export. Plus, they'd need to get the export into a phone-native format for upload onto social media, so the uploader may need admin access, familiarity with formats and/or ffmpeg, and a way to transfer to a phone or personal PC.
- ethbr1 2y ago
  > I assume these videos tend to come from the operator who only has access to view but not to export. This is why HDCP enforcement may be the dumbest legal-technical mandate ever. https://en.m.wikipedia.org/wiki/High-bandwidth_Digital_Content_Protection https://en.m.wikipedia.org/wiki/High-bandwidth_Digital_Conte... "Someone has a recording device they can point at a screen" is a low bar.
  - mrandish 2y ago
    > This is why HDCP enforcement may be the dumbest legal-technical mandate ever. Indeed. Because of HDCP common use cases like splitting, converting or sending a video signal are unsupported or afterthoughts by most consumer devices, even when dealing with non-protected signals. Of course, the HDCP flag can be removed by some shady devices but these are not commonly available and are often poorly documented.
    - tonyarkles 2y ago
      Heh, my wife and I were just talking about this the other day. She does live audio production for work but occasionally has to deal with video. Active HDMI splitters are one of the few cases where cheaper is often better because the cheap Chinese ones will usually do HDCP stripping and something sane with the EDID data, compared to more expensive ones that actually follow the spec.
      - pjc50 2y ago
        I'm a great believer in cheap Chinese technology actually having more features, since the days of region-free DVD players.
    - userbinator 2y ago
      HDCP strippers are very commonly available from the East. Of course they aren't called "HDCP strippers", but ever since the master key was leaked/cracked, many anonymous devices with HDMI inputs will strip HDCP.
ortusdux 2y ago
Are there any denoising algorithms that remove Moiré patterns? It would be a welcome addition to the stock iPhone and Android cameras.
- nihzm 2y ago
  If you don’t need it to be perfect it is actually not too difficult. A notch filter could be enough remove most of the pattern provided that you have a good way of guesstimating its frequency
  - bmicraft 2y ago
    Being very slightly out of focus would probably be the best solution
  - ortusdux 2y ago
    It looks like Adobe Raw added a dedicated moire reduction slider to their denoising features a few years back. I wonder how it operates.
MisterTea 2y ago
If its a DVR then one needs permission to download the video. Many DVR's have access policies that can limit certain users/groups to only view or playback disabling download. Then if they do have download access they likely need access to a USB port and have a USB drive handy as they likely have to download the file from a web UI. Then they have to get that video on to a PC or Phone/tablet and upload it. Or just point the phone at the screen, record, click the share button and select YouTube or whatever.
qingcharles 2y ago
The police have a never-ending issue with this when trying to get video from random Temu-quality CCTV recorders at the scene of a crime. I know one defendant who almost got away[1] with a heinous robbery on a mobile phone store because the technician from HQ remoted in to try and get the video off and somehow deleted it instead. [1] the store clerk later remembered the defendant had been drinking a pop when he entered the store and they found the bottle had been left behind, which had his DNA on it, and his DNA was on file
- squarefoot 2y ago
  > Temu-quality CCTV recorders Those DVR/NVR (including networked cameras) should be among the first things hackers should liberate from their proprietary firmware: they all use Linux but keep it tight closed and quite often phone home somewhere in China, officially to allow users connect via the phone app (another big security concern) to their cloud service, which also means the feed goes through there. One can buy the board alone by searching for "dvr board" on aliexpress and other shops; they're cheap and could be repurposed for other interesting uses because of their fast ADCs for example.
  - namibj 2y ago
    You can't just mention those ADCs without giving at least some representative specs...
    - squarefoot 2y ago
      How could I give specs about undocumented chips running a closed system? We know they can sample 1080p video, therefore they must have several MHz bandwidth. Should anyone manage to hack into the internal OS (which is Linux, albeit with closed drivers) and reverse engineer the basic drivers functions, we'd have a cheap platform to play with. As an example, I would explore the possibility to use their ADCs for multi band SDR applications, as the 8 input channel board costs only around $30. Unfortunately there are a lot of ifs, but if I had the skills I would at least attempt a reverse engineering on the cheaper model.
mrguyorama 2y ago
The more upsetting part to me is that, with even a little bit of effort, recording a screen with a camera produces a perfectly acceptable image, other than some artifacts about framerate not being synced. This was true back in the CRT and cheap Sony camcorder days, and it is even more true in the wide viewing angle, high quality phone image sensor, and image stabilization days. But nobody cares to take five extra seconds to get good framing, or reduce glare, or hold their damn phone steady, or match the damn aspect ratio! It's infuriating how little people seem to care in general
- fomine3 2y ago
  It should be able to solved by auto situation recognition on camera app.
  - dredmorbius 2y ago
    Which is getting scarily good. I realised this a couple of days ago shooting food photos, realising the color balance and saturation were way off, but that that was because in real time the camera app had recognised the subject as food. (I'm probably way late in becoming aware of this. It still simultaneously 1) blew my mind, 2) annoyed me, and 3) terrified me.)
  - pimlottc 2y ago
    That is an interesting idea! It could detect the borders of the screen, straighten and auto crop, perhaps detect and match the frames per second… if the camera resolution is high enough you could maybe even detect the original source resolution.
komali2 2y ago
When I was involved in an accident the police said they weren't allowed to give me the CCTV footage, but I was allowed to record it on my phone. Who knows.
dredmorbius 2y ago
One famous historical version of this was the live video feed from the Apollo 11 moon landing. There was a direct video feed, but that was being transmitted to Australia (facing the Moon at the time), and it wasn't possible to patch that directly through to US-compatible video feeds. The first images that Nasa received were upside down. The ultimate video, broadcast live internationally, was from a camera pointed at the CRT / television image at Honeysuckle Creek, near Canbera, ACT, Australia. I'm having trouble finding a full retelling of this though here's a story of Honeysuckle Creek's role and a bit about the TV image: <https://www.abc.net.au/news/2019-07-19/nasa-apollo-11-moon-landing-footage-sent-via-honeysuckle-creek/11273724 https://www.abc.net.au/news/2019-07-19/nasa-apollo-11-moon-l...> On the Parkes dish (Aus): <https://apollo11.csiro.au/the-australian-connection/live-from-the-moon/ https://apollo11.csiro.au/the-australian-connection/live-fro...>. The wind problem: <https://apollo11.csiro.au/the-australian-connection/delay-and-drama/ https://apollo11.csiro.au/the-australian-connection/delay-an...>. More on the technical aspects of the video feed, but without my "camera-on-a-TV-screen" bit: <https://yewtu.be/watch?v=tIogywOrv8s https://yewtu.be/watch?v=tIogywOrv8s>
- averageRoyalty 2y ago
  > Canbedra Or as we like to call our nations capital, Canberra.
  - dredmorbius 2y ago
    Yeah, typo, and well past the edit window.
- TaylorAlexander 2y ago
  I hate it when the TV signal is upside down because it is coming from Australia!
  - xen2xen1 2y ago
    I hear the go around the other way down there.
  - 2y ago

denysvitali 2y ago

This assumes that it's available in digital form. Knowing Japan, there is a chance this is an analog CCTV

Wowfunhappy 2y ago
Surely it would still be cleaner to digitize the tape (?) than to point a camera at the screen, wouldn't it?
- pistoleer 2y ago
  This was faster

accrual 2y ago

Yeah, similar for interesting events caught on security cameras. I assume these videos tend to come from the operator who only has access to view but not to export. Plus, they'd need to get the export into a phone-native format for upload onto social media, so the uploader may need admin access, familiarity with formats and/or ffmpeg, and a way to transfer to a phone or personal PC.

ethbr1 2y ago
> I assume these videos tend to come from the operator who only has access to view but not to export. This is why HDCP enforcement may be the dumbest legal-technical mandate ever. https://en.m.wikipedia.org/wiki/High-bandwidth_Digital_Content_Protection https://en.m.wikipedia.org/wiki/High-bandwidth_Digital_Conte... "Someone has a recording device they can point at a screen" is a low bar.
- mrandish 2y ago
  > This is why HDCP enforcement may be the dumbest legal-technical mandate ever. Indeed. Because of HDCP common use cases like splitting, converting or sending a video signal are unsupported or afterthoughts by most consumer devices, even when dealing with non-protected signals. Of course, the HDCP flag can be removed by some shady devices but these are not commonly available and are often poorly documented.
  - tonyarkles 2y ago
    Heh, my wife and I were just talking about this the other day. She does live audio production for work but occasionally has to deal with video. Active HDMI splitters are one of the few cases where cheaper is often better because the cheap Chinese ones will usually do HDCP stripping and something sane with the EDID data, compared to more expensive ones that actually follow the spec.
    - pjc50 2y ago
      I'm a great believer in cheap Chinese technology actually having more features, since the days of region-free DVD players.
  - userbinator 2y ago
    HDCP strippers are very commonly available from the East. Of course they aren't called "HDCP strippers", but ever since the master key was leaked/cracked, many anonymous devices with HDMI inputs will strip HDCP.

ortusdux 2y ago

Are there any denoising algorithms that remove Moiré patterns? It would be a welcome addition to the stock iPhone and Android cameras.

nihzm 2y ago
If you don’t need it to be perfect it is actually not too difficult. A notch filter could be enough remove most of the pattern provided that you have a good way of guesstimating its frequency
- bmicraft 2y ago
  Being very slightly out of focus would probably be the best solution
- ortusdux 2y ago
  It looks like Adobe Raw added a dedicated moire reduction slider to their denoising features a few years back. I wonder how it operates.

MisterTea 2y ago

If its a DVR then one needs permission to download the video. Many DVR's have access policies that can limit certain users/groups to only view or playback disabling download. Then if they do have download access they likely need access to a USB port and have a USB drive handy as they likely have to download the file from a web UI. Then they have to get that video on to a PC or Phone/tablet and upload it. Or just point the phone at the screen, record, click the share button and select YouTube or whatever.

qingcharles 2y ago

The police have a never-ending issue with this when trying to get video from random Temu-quality CCTV recorders at the scene of a crime. I know one defendant who almost got away[1] with a heinous robbery on a mobile phone store because the technician from HQ remoted in to try and get the video off and somehow deleted it instead. [1] the store clerk later remembered the defendant had been drinking a pop when he entered the store and they found the bottle had been left behind, which had his DNA on it, and his DNA was on file

squarefoot 2y ago
> Temu-quality CCTV recorders Those DVR/NVR (including networked cameras) should be among the first things hackers should liberate from their proprietary firmware: they all use Linux but keep it tight closed and quite often phone home somewhere in China, officially to allow users connect via the phone app (another big security concern) to their cloud service, which also means the feed goes through there. One can buy the board alone by searching for "dvr board" on aliexpress and other shops; they're cheap and could be repurposed for other interesting uses because of their fast ADCs for example.
- namibj 2y ago
  You can't just mention those ADCs without giving at least some representative specs...
  - squarefoot 2y ago
    How could I give specs about undocumented chips running a closed system? We know they can sample 1080p video, therefore they must have several MHz bandwidth. Should anyone manage to hack into the internal OS (which is Linux, albeit with closed drivers) and reverse engineer the basic drivers functions, we'd have a cheap platform to play with. As an example, I would explore the possibility to use their ADCs for multi band SDR applications, as the 8 input channel board costs only around $30. Unfortunately there are a lot of ifs, but if I had the skills I would at least attempt a reverse engineering on the cheaper model.

mrguyorama 2y ago

The more upsetting part to me is that, with even a little bit of effort, recording a screen with a camera produces a perfectly acceptable image, other than some artifacts about framerate not being synced. This was true back in the CRT and cheap Sony camcorder days, and it is even more true in the wide viewing angle, high quality phone image sensor, and image stabilization days. But nobody cares to take five extra seconds to get good framing, or reduce glare, or hold their damn phone steady, or match the damn aspect ratio! It's infuriating how little people seem to care in general

fomine3 2y ago
It should be able to solved by auto situation recognition on camera app.
- dredmorbius 2y ago
  Which is getting scarily good. I realised this a couple of days ago shooting food photos, realising the color balance and saturation were way off, but that that was because in real time the camera app had recognised the subject as food. (I'm probably way late in becoming aware of this. It still simultaneously 1) blew my mind, 2) annoyed me, and 3) terrified me.)
- pimlottc 2y ago
  That is an interesting idea! It could detect the borders of the screen, straighten and auto crop, perhaps detect and match the frames per second… if the camera resolution is high enough you could maybe even detect the original source resolution.

komali2 2y ago

When I was involved in an accident the police said they weren't allowed to give me the CCTV footage, but I was allowed to record it on my phone. Who knows.

dredmorbius 2y ago

One famous historical version of this was the live video feed from the Apollo 11 moon landing. There was a direct video feed, but that was being transmitted to Australia (facing the Moon at the time), and it wasn't possible to patch that directly through to US-compatible video feeds. The first images that Nasa received were upside down. The ultimate video, broadcast live internationally, was from a camera pointed at the CRT / television image at Honeysuckle Creek, near Canbera, ACT, Australia. I'm having trouble finding a full retelling of this though here's a story of Honeysuckle Creek's role and a bit about the TV image: <https://www.abc.net.au/news/2019-07-19/nasa-apollo-11-moon-landing-footage-sent-via-honeysuckle-creek/11273724 https://www.abc.net.au/news/2019-07-19/nasa-apollo-11-moon-l...> On the Parkes dish (Aus): <https://apollo11.csiro.au/the-australian-connection/live-from-the-moon/ https://apollo11.csiro.au/the-australian-connection/live-fro...>. The wind problem: <https://apollo11.csiro.au/the-australian-connection/delay-and-drama/ https://apollo11.csiro.au/the-australian-connection/delay-an...>. More on the technical aspects of the video feed, but without my "camera-on-a-TV-screen" bit: <https://yewtu.be/watch?v=tIogywOrv8s https://yewtu.be/watch?v=tIogywOrv8s>

averageRoyalty 2y ago
> Canbedra Or as we like to call our nations capital, Canberra.
- dredmorbius 2y ago
  Yeah, typo, and well past the edit window.
TaylorAlexander 2y ago
I hate it when the TV signal is upside down because it is coming from Australia!
- xen2xen1 2y ago
  I hear the go around the other way down there.
- 2y ago