how to write and read pgm p5 file in java -

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i want read pgm file. kept image content in byte array. when accessed pixels, see values negative. so, applied "& 0xff" each byte. hope ok when write file, isn't same original image.

how can read , write pgm p5 file?

int = bytearray[index] & 0xff; //reading writer.write((char)(i)); //bufferedwriter

keep in mind p5 format binary. using writer , cast value char. text, not binary data.

instead, use outputstream , write value in i directly stream.

int = bytearray[index] & 0xff; // reading stream.write(i); // outputstream

ps: if don't feel implementing pgm format yourself, have created imageio plugin netpbm formats (pnm) use. it's open source (bsd license).


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