Using pandora as an HD camcorder

[NebulaUK]

If you attach a webcam to the pandora could it take hd or near hd video and record it. If not could someone make this functionality happen i think it would be really cool.

 

[WizardStan]

I don't know about HD, but I connected a webcam at 640x480 to my Pandora and it was quite good. What webcam did you have in mind?

 

[NebulaUK]

i am just talking theoretically at the moment as i would like to get a pandora. would it be possible to record hd I know it may not be possible to play it back. ideally i would like a webcam that could clip on top of the pandoras screen.

 

[WizardStan]

It depends entirely on the webcam. It's probably possible that you could simply stream the output of the webcam directly to the SD card without touching the CPU very much, so yes. If you wanted to display the image at the same time, that would require a lot more CPU and you may not be able to do it with HD, but it depends entirely on what format the webcam provides its video in.

 

[NebulaUK]

thanks for all help so far do u recommend any specific webcam for this.

 

[NebulaUK]

would this one be any good Trust Widescreen HD Webcam 16530

 

[NebulaUK]

Please could anyone make some suggestions for me and how I would go about doing this.

 

[Prometheus]

I mean absolutely no disrespect in saying this (it's not in my nature), but have you tried Googling about it during the couple of days since your last post?


No, seriously, I'm not being a git. Whenever I want to know if something will work with Linux (which is my primary operating system, so I do have to check these things on occasion), I search for the product name or model number, along with the term "Linux" or "Ubuntu". (Even though the Pandora doesn't use it, Ubuntu is a popular Linux distribution, and they have a wealth of information on their forums, a large amount of which can be applied to any machine running any flavour of Linux, so in my humble opinion it's always worth using that as a search term when researching a purchase.)


I've just had a look around for results relevant to the webcam you mentioned, but I'm not finding anything useful or informative. When this occurs, personally I would take it as a red flag and start looking for a different product. Have you got any others in mind?

 

[NebulaUK]

Ok nevermind but I guess what I really want to now is is the CPU in the Pandora powerful enough to capture HD and maybe display a few frames a second on the screen for purposes of knowing what the camera is seeing.

 

[WizardStan]

Yes. If the driver is done right, recording from the camera should not be very CPU intensive: it would basically just stream data off the camera and directly onto the SD card. Displaying it at the same time, however, will be CPU intensive since it actually needs to decode the stream. Some tricky work would be required to do both at the same time.

 

[NebulaUK]

ok thanks but would it be possible to display the image on screen at a reduced frame rate so you can see what the camera is capturing

 

[gadgetoid]

The technical complexities associated with accomplishing what you're asking would require a significant time investment from someone who knows what they're doing, or at least is willing to give it a crack.


Yes, it's theoretically possible to steam HD video straight from the camera onto an SD card and, yes, it would probably be possible to grab every N frames of that data and display it on screen. But unless you're going to start programming yourself, or trying to cobble together some existing source to accomplish this, you're probably never going to see it happen.


I recommend you pick up an HD webcam, and start from there. The trust you mention, assuming it'll work with the Pandora (I've no idea!) looks like a fairly cheap, yet reasonably good quality place to start.


If you're lucky, software to capture HD video is already just a ./configure port away. Google harder!

 

[TitanUranus]

Is there no easy way just to use some kind of "preview" window with a shitty low resolution that would give an indication of what you have in the frame in at ant given moment? I can't believe my camera actually has to decode the full HD resolution just to display it on the low res LCD when I'm taking a movie.

 

[WizardStan]

No easy way, no. By default, webcam devices in Linux are single connection only: only one application can read from the webcam at a time.


Second to that, applications weren't designed with that kind of design in mind. Either they're playing back a prerecorded video, or recording an input stream: it doesn't make sense in most use cases to be able to display on some of what's being recorded. There are applications that will decode the stream AND record it to hard drive, but it tries to decode the entire stream: I'm not sure what would happen if it tried to record more than the CPU could keep up with.


The "quick and easy" solution is to write a wrapper device driver, one that opens the webcam itself but allows multiple processes to open it up. There's a few programs that already do this, but I can't think of them off the top of my head. In this way, you could start a record application, and then start mplayer to display, and renice the two processes so mplayer doesn't clobber the record.


The reason your camera can do it is because that's how it was designed.

 

[dreamer]

It also kind of depends on what you mean with "HD".

 

[Valpskott]

I was looking for some Software to record my webcam from my Pandora(which is arriving today).


Do anyone know if I can get a hold on guvcview for the pandora?


I have 2 webcams, one is old and shitty, and the other one is a Logitech c910 able to Capture HD, so I can give it a shot if I find any software. And a possibly work around for your problem(that I might try) is connecting both cams, The better one used for recording and the crappy one for viewing at lower fps and resolution.


Edit:


I wanted to add that the c910 works great with guvcview in Ubuntu(Gnu/Linux) on normal desktops/laptops. The only troublesome part I've had with it is configuring the right codecs in guvcview. I've found that using mjpg as both input and output is the most trouble free thing to do in regard to video/audio sync, but I've yet to come across an video-editor that likes the format, so I usually recode it twice(first with ConvertOGG into OGV format) then ffmpeg into mpeg4 which kdenlive handles really well.

 

[WizardStan]

I was looking for some Software to record my webcam from my Pandora(which is arriving today).

mplayer. It can open the webcam and then output directly to a file. dumpstream and dumpfile are the options you want.


Unfortunately I haven't figured out how to get it to dumpstream and display the video at the same time. If it could do that it's be downright amazing.

 

[DFP]

Just... use normal or even mini HD cam.


I don't know why you'd want to add a screen + connecting cable to the mix and do this balancing act when you can get a nice pocket camera that records HD better than webcam/quality. They're cheap enough today.

 

[Wootson]

Just... use normal or even mini HD cam.


I don't know why you'd want to add a screen + connecting cable to the mix and do this balancing act when you can get a nice pocket camera that records HD better than webcam/quality. They're cheap enough today.

I can only approve this comment, because that's just the way it is. A webcam is maybe half the price of a decent HD pocket video camera, but still not as convenient. There can be problems with lots of things during the process of recording and creating data dumps of recordings as well. I'd just go with a small camera with a simple SD card. Pop it into the Pandora and enjoy (with the codec pack installed first).

 

[Valpskott]

I was looking for some Software to record my webcam from my Pandora(which is arriving today).

mplayer. It can open the webcam and then output directly to a file. dumpstream and dumpfile are the options you want.


Unfortunately I haven't figured out how to get it to dumpstream and display the video at the same time. If it could do that it's be downright amazing.

Ahh, thanks for the advice. I succesfully opened (and watched) a stream in the resolution of 800x480(Pandora screen resolution)

mplayer -tv driver=v4l2:gain=1:width=840:height=480:device=/dev/video0:fps=20:outfmt=yuy2 tv://

Going any higher and mplayer ended with an error basically saying it couldn't open a screen larger then the screen resolution.



So, I thought, how about outputting it into a file instead, so I tried -dumpfile and it looked all good, except there where no file in the directory I had specified.

mplayer -tv driver=v4l2:gain=1:width=1280:height=720:device=/dev/video0:fps=20:outfmt=mjpg tv:// -dumpfile /media/DD/video/dump2.avi

Tried googling but never found someone trying to record a video-device in mplayer.


Any help would be greatly apprechiated