Camera quality low with MMAPI!

[JTierno]

This is an answer to mshelwa. The image that is shown in the MIDlet is the one placed in the "camera" folder named "camera.xxx", being xxx the format of the image (png, jpg or whatever).

You will have noticed you have a camera.bmp file, a camera.png file and a camera.jpg file. if you call getSnapshot("null") or getSnapshot("encoding=png"), you will get camera.png. If you call getSnapshot("encoding=bmp"), you will get camera.bmp. The emulator just passes the right image to the application, it does not transform the format (nor the size, I believe) of the image. You just get what you place in the folder.

On the other hand, the viewfinder.jpg file is the image you see when the camera is on, before the use of get snapshot.

What I do is place the image I want to use in the folder and rename it as "camera.png". Yes, if I want to change the image I have to rename all the files...

If anyone knows a better way of doing this, please let me know.

By the way, I would also be interested in a 640x480 image in the real terminal (3650 and also 6600), so, Nokia people or whoever can, please, hear our call...

[cfrasci]

Hi JTierno

you can have a 640*480 Image on the terminal using

image = videoControl.getSnapshot("encoding=jpeg&width=640&height=180");

for me it works on the 3650! but be patient, the device is very slow in creating the image because of its size!

greez
cfrasci

[luemkemann]

I think the issue here is the quality, not the size. Of couse you can get 640x480 images, but the quality is so unbelievably bad, it's unusable.

[JTierno]

Cfrasci, can you please tell me your firmware version? (as you know, you get it by typing *#0000#) .

Maybe it is a question of firmware version, as different people on this thread has achieved different resolutions...

Mine is version 2.50, 13-02-2003, NHL-8. But to tell you the truth, I must still check what resolution do I get.

Any one else with the same problem, could also send the version, so we can together come to a conclusion?

Thank you very much

[cfrasci]

Hi JTierno

I let update the firmware yesterday to V 3.16, 20-05-2003, NHL-8!
I had the same firware as you before. But I tested it again, the quality is still poor...

best regards
cfrasci

[jones139@ntlworld.com]

I have been trying to find out what snapshots are available on the 3650 by using something along the lines of:
String fmts = System.getProperty("video.snapshot.encodings")

The API documentation suggests that this should give you information about the available resoluctions and formats of the image, but when I run it, it only gives the available formats (png, jpeg or bmp) - nothing about resolution or colour depth.

If I call videoControl.getSnapshot("encoding=bmp") I get an image with only 8 bit colour depth (ie 256 colours), whereas the camera is supposed to be capable of 24 bit colour depth. I think this is the problem described in the above posts.

The API documentation says that the format should be specified in a 'special format' which includes information about the colour depth (e.g. gray8, rgb888 etc.).

Is there another call to System.getProperty that specifies the available colour depths, or easier still, is there any good documentation on the 3650's MMAPI implementation that specifies these things?

I have been looking into how you would write an application in C++ on the 3650, and I have come to the conclusion that it should be possible to get 24 bit colour images in C++. It would be really nice to know if this was the only way to to it, or if it is possible in Java.

[JTierno]

I haven´t tested the bmp format, but in png format you do get a 24-bit depth image.

And I have no idea of what method to call to know the available resolutions.

[jones139@ntlworld.com]

Thank you for that - I guess I'd better go and learn how to interpret png data - I only used BMP because it was easy to decode!

Cheers
Graham

[lidongtao]

Has anyone tried to use MMAPI to take picture on 6600? how is the quality? I am going to develop a midlet on it, but if the image quality is very low, i'd better drop it

[JTierno]

Hello lidongtao

I´m also going to work with a 6600 in the near future, but I haven´t still put my hands on one . So when you know something about its image quality, please tell us.

And this one goes for Graham (jones139@...). I have already taken the pixels from a png file, and it´s quite easy as it is nos filtered, compressed nor interleaved (as it could be), you just have to take the headers out. Take a look to the png specifications, and take into account that, in the phone, each scanline is packed into a "deflate" block.

Anyway, it sounds quite strange for me that bmp format has only 256 colors, I´d be sure of that first.

[jones139@ntlworld.com]

I was surprised at the BMP format only being 256 colours too, but the header lengths etc. are all correct for that being the case, and the pixels appear to be in the right position when I read them, so I think it is true. I'll look into decoding the PNG format as you say it is easy!

Graham.

[sbwoodside]

Has anyone tried this with 6600 yet? Since it has MIDP 2.0 and also, more RAM, I would expect the quality to be better.

Especially since perhaps RAM is a factor since java uses more ram to do the same things than C++ does...

simon

[JTierno]

I am currently working with the 6600 phone. The resolution you can get is the same as the 3650, that is, 160*120. I believe it has to do with Symbian OS and with the nature of the camera chipset of the phone.

I have seen the specifications of some VGA camera chipset like the ones used for a mobile phone (don´t know it exactly the same model, it would be nice if anyone who knows more about this dropped a message), and it uses two resolutions, VGA (640*480) for the photographs and QQVGA (160*120) for video and for the viewfinder.

Besides, a typical native Symbian application that uses the camera, can choose between one of these modes, and the programmer must make the viewfinder him/herself if s/he wants one.

On the other hand, it seems the MMAPI uses the stream of video (made in QQVGA quality) to take the snapshot; it does not stop the video capture, then takes a photograph at a different mode, and then keeps on capturing video. It simply extracts a frame from the video stream.

I have to say that the 6600 does work better as the white balance does not distort colours so much, achieving a slightly better image quality.

There is a new Nokia phone, the 7610, which has a 1 megapixel camera, and also has the MMAPI. Probably you can make a lot more with this phone. ¿Has anyone put his /her hands on it?

[ppe_manager]

I believe what JTierno said is true
i tested both 6600 and 3650 and you get low quality

but 6600 camera implements a numerical Zoom

does anyone know if it is possible to activate the zoom through java?

[JTierno]

you can specify any dimension you wish in getSnapshot(), it will be created as long as there is memory enough. But I believe it is only the same 160x120 image rescaled, so the information you have is the same. That is why the quality is poor.

Jonatan Tierno.