libjpeg8 include are those two functions, but in libjpeg-turbo has the following:
//jconfig.h
#define JPEG_LIB_VERSION 62
...
//jpeglib.h
#if JPEG_LIB_VERSION >= 80
/* Data source and destination managers: memory buffers. */
EXTERN(void) jpeg_mem_dest JPP((j_compress_ptr cinfo,
unsigned char ** outbuffer,
unsigned long * outsize));
EXTERN(void) jpeg_mem_src JPP((j_decompress_ptr cinfo,
unsigned char * inbuffer,
unsigned long insize));
#endif
if i try to use "JPEG_LIB_VERSION 80" i'll get the following:
error LNK2019: unresolved external symbol _jpeg_mem_src referenced in function ...
so, how can i use those functions if it possible? do i need compile some package of libjpeg-turbo?
The precompiled .lib and .dll files only support the version 6 functions. You need to compile your own library. Pass the -DWITH_JPEG8=1 flag to CMake to get those two functions.
来源：https://stackoverflow.com/questions/11070473/how-can-i-use-jpeg-mem-src-jpeg-mem-dest-in-libjpeg-turbo