libjpeg

Okay, so I had an earlier problem with PIL that is still unresolved. Someone else had this problem and had success by removing the old JPEG library . I can't really do that on my machine, however, as it's RHEL and so many things are dependent on libjpeg and libjpeg-devel (when I tried yum remove libjpeg just to see, there were a total of 252 packages that would have been removed!) I have jpeg-8 installed in /usr/local/lib. It's correctly being used by python, but not by apache. Here's a list from lsof: COMMAND PID USER FD TYPE DEVICE SIZE NODE NAME httpd xxxxx root mem REG 253,3 xxxxx0 xxxxx34

Does libjpeg allows/have routines to scale the output image? I have an image which needs to be resized when saving to and loading from, Providing width1, height1 on input and getting width2, height2 on output, and I really cant use anything outside. Yes, libjpeg does support image scaling, but with some limitations. Libjpeg version 8c and higher supports M/8 scaling where M is an integer between 1 and 16. The more commonly used libjpeg version 6b supports M of 1, 2, 4, and 8 only (i.e. power-of-2 downscaling). Supply the scaling numerator and denominator to the decompression object using scale

Ater compiling libjpeg and then using it, I stumbled upon the problem: JPEG parameter struct mismatch: library thinks size is 512, caller expects 492 after which the program halts. This happens specifically with the structs struct jpeg_decompress_struct and struct jpeg_compress_struct . If the checks are removed on these structs, the program crashes with a null pointer exception, and the struct members contain garbage. The error occurs with either precompiled binaries from version 6b, or with precompiled version 9a, and with the compiled version 9a; compiled with MinGW, MSYS 1.0, on windows

I have JPEG compressed byte stream stored in a variable called "Image" and I want to convert this byte stream to RGB. Eg: unsigned char *Image; My question is: Is there any way to pass "Image" to jpeg_stdio_src() to get the RGB color values? Can anyone tell me how I could use jpeglib library to get RGB from byte stream "Image"? Thank you Try something like this. This uses an object currImage to store the results (not declared here). typedef struct { struct jpeg_source_mgr pub; // public fields JOCTET * buffer; // start of buffer boolean start_of_file; // have we gotten any data yet? } my

I'm trying to load part of big JPEG file (hundreds of megapixels) with a limited memory footprint. I need only about a 1000 scanlines of 20000. It seems that current implementation of libjpeg (as well as its fork libjpeg-turbo) doesn't provide a way to skip unneeded 19k scanlines without decoding them. Is there a workaround for it without digging into libjpeg internals? Partial JPEG decoding was implemented in jpeglib-turbo one year ago. I didn't try it, but I guess it should work. Check it: Add further partial decoding optimization #34 You can't avoid having to decode the scan lines you want

I am having some trouble getting Django & PIL work properly since upgrading to Snow Leopard. I have installed freetype, libjpeg and then PIL, which tells me: --- TKINTER support ok --- JPEG support ok --- ZLIB (PNG/ZIP) support ok --- FREETYPE2 support ok but when I try to upload a jpeg through the django admin interface I get: Upload a valid image. The file you uploaded was either not an image or a corrupted image. It works fine with PNG files. Any Ideas? Cato I had the same experience with Leopard 10.5.x Here is what I did to fix it, (may not work for you). Go to your PIL working folder

I am using Libjpeg version 6b. In version 8 they have a nice function to read data out of the memory called jpeg_mem_src(...) , unfortunately ver. 6b does not have this function. What can I use to read compressed data directly from memory? All I see is jpeg_stdio_src which reads from the hard drive. Write your own... /* Read JPEG image from a memory segment */ static void init_source (j_decompress_ptr cinfo) {} static boolean fill_input_buffer (j_decompress_ptr cinfo) { ERREXIT(cinfo, JERR_INPUT_EMPTY); return TRUE; } static void skip_input_data (j_decompress_ptr cinfo, long num_bytes) {