My j2me application must take a photo, edit it a little and save it somewhere (or send to server).
Camera return me bytes of an image in jpg format, but after I create an Image object from it (using Image.createImage()), I could not pack it back to jpg.
Is there any jpeg encoders for j2me?
I found one written in j2se, but it uses j2se-specific classes.
This can be done! Even without any proprietary APIs or libraries. This can be achieved if your phone supports JSR 234 and has the ability to process JPEG files through it. You do this:
//Create MediaProcessor for raw Image
MediaProcessor mediaProc = GlobalManager.createMediaProcessor("image/raw");
//Get control over the format
ImageFormatControl formatControl = (ImageFormatControl)
mediaProc.getControl("javax.microedition.amms.control.ImageFormatControl");
//Set necessary format
formatControl.setFormat("image/jpeg");
Then you set input Image, output stream and start the media processor. Voila! You have saved your image in JPEG.
By the way, since JSR 234 is not supporting on many devices, I take Sun's JIMI image library and port JPEG-encoding part to j2me. It works fine and doesn't use too much memory.
It is purely implementation dependent, some devices allow you to create an Image object using a jpg file while others don't. However Sun's spec says that devices must support png, however others are at the discretion of the OEM manufacturers
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My Linux gcc program is generating an image as a two dimensional array of pixel data, that I want to print out through CUPS.
The available CUPS_FORMAT_??? is very dicouraging. Tried CUPS_FORMAT_AUTO and send the image as TIFF, it failed. The TIFF data is verified by making perfectly viewable .TIF of it. Making JPEG is far too complicated, but can CUPS_FORMAT_RAW be used? I fails to find a spec of what to feed the cupsWriteRequestData() with using this format. All searches ends up with priner side stuff, nothing about client API. Any help, please?
I'm building a project where people can upload files, I would like to then display those files in a browser where people can interact with them (vote, comment etc)
However, this means I need to programatically build the html depending on the format of the video or image. Is there a way to feed a file (or filename) into a library, and determine whether I need to display it in a video element or an image element? Even a list of video formats vs image formats would help but I haven't seen anything in regards to that.
No module can reliably determine the file type. The user could either change the extension or even the magic number of the file to obfuscate it. The only reliable way it to try to pass file to some image / video transcoder to let it decide or error out if the format is invalid. This way you know you are working with known formats since all files are transcoded to your specific extensions. That could be mp4 or png. I recommend using handbrake for videos and sharp for images. Leaving the NPM links down below:
https://www.npmjs.com/package/handbrake-js
https://www.npmjs.com/package/sharp
.
I am trying to understand how mpd file plays and i am referring to the following data set:
http://www-itec.uni-klu.ac.at/ftp/datasets/mmsys12/Valkaama/MPDs/Valkaama_1s_act_isoffmain_DIS_23009_1_v_2_1c2_2011_08_30.mpd
In mpd file format there is segment base consists of mp4 chunk and within it has chunk list with extension .m4s.I downloaded mpd file using :
http://www-itec.uni-klu.ac.at/ftp/datasets/mmsys12/Valkaama/valkaama_1s/valkaama_1s_50kbit/valkaama_50kbit_dash.mp4
and m4s chunk by following link:
http://www-itec.uni-klu.ac.at/ftp/datasets/mmsys12/Valkaama/valkaama_1s/valkaama_1s_50kbit/valkaama_1s1.m4s
I tried to play both mp4 and m4s in vlc player but not able to play any of these two so i want to ask which of the chunk links in the mpd file forma i can be able to play standalone in vlc player.
Please correct me if any of my observations is wrong:
Regards
Mayank
MPD file is just a index of streams with various formats in order to adapt to your bandwidth, to get more information follow the links of the other answers here.
It's possible to download all streams and merge them into a single file, you could achieve this by using youtube-dl:
youtube-dl http://URL/TO/manifest.mpd
You can get more information in https://stackoverflow.com/a/39931712/1522342.
Also, VLC 3.0.0+ can play that kind of file from a url, just open VLC, use the shortcut CTRL+N, paste the url and enjoy.
A DASH player plays an MPD by selecting a Period, and in the Period one or more AdaptationSet, and then one Representation per AdaptationSet. For the chosen Representation, it downloads and passes the intialization segment and some media segments to the media engine. As indicated by others you can simulate that by concatenating (simply using caton Linux).
The MPEG-DASH standard requires that initialization segments (in your case the mp4 file) contain no data. This is because when switching the player might use several times the initialization segment. You can open it in a player but it does not contain any media.
For m4s files, they contain media data but they cannot be interpreted without the associated initialization segment.
you can download init segment (SegmentBase/Initialization#sourceURL) and all media segments (SegmentList/SegmentURL#media) and concatenate everything (e.g. with the copy command on windows). The result should be playable on VLC. This has to be done for audio and video separately. In the next step you can then use MP4Box or similar tools to mux audio and video.
Alternatively you can use www.dash-downloader.com to download everything in one step. The page will display some log explaining what it's doing. That might be helpfull.
(full disclosure: that's my website).
I dont think it is possible to play any of the files in a standalone player. The mp4 is the init segment which is required to decode the .m4s media segments. I dont think there is an option in the vlc player to map an init segment to multiple media segments. Nevertheless you can try a Dash player to play the manifest file. For instance dash.js
Initialization segment: A sequence of bytes that contain all of the initialization information required to decode a sequence of media segments. This includes codec initialization data, Track ID mappings for multiplexed segments, and timestamp offsets (e.g. edit lists).
Media segment: A sequence of bytes that contain packetized & timestamped media data for a portion of the media timeline. Media segments are always associated with the most recently appended initialization segment.
Source: http://www.w3.org/TR/media-source/#init-segment
I would like to convert .rm (RealPlayer Media) file to MP3 or another format?
First, I successfully managed that using VLC but the quality was not good. Then I tried the Real Alternative codec with DirectShow, this also worked ok, but then I found that the codec is no longer developed because RealNetworks sued the developer.
Now, I have installed the RealPlayer and I am trying to use it's DirectShow filters to convert .rm to .mp3 but without success:( (Actually after adding RealPlayer Transcode filter and choosing a file the GraphStudio crashes.)
Is there a legal way to programmatically convert .rm file to another format? How to make RealPlayer to programmatically convert files? Do you have any hints or examples, how to use RealPlayer Transcode filter? (I am new to DirectShow.)
UPDATE to make the question more concrete: How can I list implemented interfaces and its members of RealPlayer Transcode filter? I have not found any documentation:( (The GraphStudio says it has 0 pins and just common properties.)
You need to build a DirectShow graph to read and decode .rm, then compress audio into MP3 and write it into a file. This is similar to recompressing an AVI file, described in some detail on MSDN: Recompressing an AVI File. You just have audio without video there, and the container formats are different.
UPDATE: There is no way to reliably list implemented interfaces in COM. Sometimes you can find this out by checking the type library, however a lot of DirectShow filters are coming without it. Typically, you need an SDK header file from the filter vendor to get a definition of implemented so called 'private' interfaces.
I want to save an image in EXIF format using System.Drawing.Image.Save or a similar method in a C# application using .NET framework v3.5. The MSDN documentation lists EXIF as an option for ImageFormat. However, it does not seem to be supported - at least not without some configuration unknown to me. When I enumerate the built-in encoders via ImageCodecInfo.GetImageEncoders() EXIF is not included. (Built in encoders on my machine (Vista Ultimate x64) are: BMP, JPEG, GIF, TIFF, and PNG.) If I save an image using the ImageFormat.Exif property, I simply get the default PNG format.
How can I save an image in EXIF format using .NET 3.5?
EXIF isn't a image file format per se, but a format for meta-data found within JPEG images conforming to the DSC (Digital Still Camera) standard as specified by JEITA.
GDI+ (i.e. Microsoft .NET Framework) allows you to read/write metadata image properties via the Image.PropertyItems, however the EXIF properties exposed by GDI+ are pretty cumbersome and don't convert the values the way you would expect. A lot of work is actually needed to be able to natively read/write these values (e.g. you'd need to unpack binary fields containing specially encoded values according to the JEITA spec).
A straight-forward open-source library which implements all the standard EXIF properties can be found at http://code.google.com/p/exif-utils/ This is probably the easiest way to do this. See the simple included demo which reads in a file, prints out all the EXIF properties and then adds a property to the image.
Have you seen this: Lossless JPEG Rewrites in C#