FileInputStreams and UDP packets revisited.

Question

Sorry about the second post, but some issues have arisen that I just cannot seem to solve.
I'm trying to take a raw image file that will act as a video frame and read it in to an internal buffer. From there, I need to extract the header from the file (see below for header format) and set some variables based on the header. After that, I need to use those variables to create individual headers for each packet that I'm going to send to the video client and send the rest of the data with 32kbyte packets.
I understand that FileInputStream has a read() method that will read in an array of bytes up to it's length, and it seems to be the easiest way to do it, but my dilemma is in dissecting the file and extracting the header from it.
The image (ppm format) file looks like so:
P3
50 50
255
0 0 70 0 0 70 0 0 70 0 0 70 0 0 70 etc.
Where "P3" on a line by itself is a verification that this is indeed a PPM file
"50 50" on a line by itself is the xwidth and ywidth of the raster of pixels
"255" on a line by itself is the max RGB color value
After that, the data follows which is a raster of pixels made up of 3 bytes, one for Red, one for Green, one for Blue, with an unknown amount of whitespace only between the blue value of one pixel and the red value of the next.
I apologize for the lengthy topic but I hope it may incite some debate and get some people thinking maybe!? Because it sure did stump me. Any help is greatly appreciated. Thanks a lot, folks!

Answer 1

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Initially, my problem was just reading in the file, now I'm unsure what the best way is to extract the header from the raster of pixels from an array of bytes, or if there's a way I can read it in as strings, or if I should read it in as an array of chars, or what. Here's the link to the original thread if necessary:
Why do you want to read it in as strings? i hope that the video data is not stored in the file as strings! As if it is then it is wasting a huge amount of space, nearly twice the space that is needed.
When you say that ## is on a line by it self you mean that it seperated by a line feed? if it is then it means that you are using a text file to store the video data which is a waste. Or is the ppm format a hybrid text binary file? i am not familar with the format.
If it is firstly text and then binary then use a buffered reader to read in three lines for the "P3", "50 50" and "255" and then directly read the bytes from the rest of the file.