AlbumShaper
1.0a3
|
Go to the source code of this file.
Defines | |
#define | NEXTBYTE() getc(infile) |
#define | M_SOF0 0xC0 |
#define | M_SOF1 0xC1 |
#define | M_SOF2 0xC2 |
#define | M_SOF3 0xC3 |
#define | M_SOF5 0xC5 |
#define | M_SOF6 0xC6 |
#define | M_SOF7 0xC7 |
#define | M_SOF9 0xC9 |
#define | M_SOF10 0xCA |
#define | M_SOF11 0xCB |
#define | M_SOF13 0xCD |
#define | M_SOF14 0xCE |
#define | M_SOF15 0xCF |
#define | M_SOI 0xD8 |
#define | M_EOI 0xD9 |
#define | M_SOS 0xDA |
#define | M_APP0 0xE0 |
#define | M_APP12 0xEC |
#define | M_COM 0xFE |
#define | READ_BINARY "rb" |
Functions | |
bool | process_SOFn (int &width, int &height) |
bool | skip_variable () |
bool | read_1_byte (int *res) |
bool | read_2_bytes (unsigned int *res) |
bool | first_marker (int *res) |
bool | next_marker (int *res) |
bool | getJPEGSize (const char *filename, int &width, int &height) |
Variables | |
FILE * | infile |
#define M_APP0 0xE0 |
Definition at line 42 of file jpegSize.cpp.
#define M_APP12 0xEC |
Definition at line 43 of file jpegSize.cpp.
#define M_COM 0xFE |
Definition at line 44 of file jpegSize.cpp.
#define M_EOI 0xD9 |
Definition at line 40 of file jpegSize.cpp.
Referenced by getJPEGSize().
#define M_SOF0 0xC0 |
Definition at line 26 of file jpegSize.cpp.
Referenced by getJPEGSize().
#define M_SOF1 0xC1 |
Definition at line 27 of file jpegSize.cpp.
Referenced by getJPEGSize().
#define M_SOF10 0xCA |
Definition at line 34 of file jpegSize.cpp.
Referenced by getJPEGSize().
#define M_SOF11 0xCB |
Definition at line 35 of file jpegSize.cpp.
Referenced by getJPEGSize().
#define M_SOF13 0xCD |
Definition at line 36 of file jpegSize.cpp.
Referenced by getJPEGSize().
#define M_SOF14 0xCE |
Definition at line 37 of file jpegSize.cpp.
Referenced by getJPEGSize().
#define M_SOF15 0xCF |
Definition at line 38 of file jpegSize.cpp.
Referenced by getJPEGSize().
#define M_SOF2 0xC2 |
Definition at line 28 of file jpegSize.cpp.
Referenced by getJPEGSize().
#define M_SOF3 0xC3 |
Definition at line 29 of file jpegSize.cpp.
Referenced by getJPEGSize().
#define M_SOF5 0xC5 |
Definition at line 30 of file jpegSize.cpp.
Referenced by getJPEGSize().
#define M_SOF6 0xC6 |
Definition at line 31 of file jpegSize.cpp.
Referenced by getJPEGSize().
#define M_SOF7 0xC7 |
Definition at line 32 of file jpegSize.cpp.
Referenced by getJPEGSize().
#define M_SOF9 0xC9 |
Definition at line 33 of file jpegSize.cpp.
Referenced by getJPEGSize().
#define M_SOI 0xD8 |
Definition at line 39 of file jpegSize.cpp.
Referenced by first_marker().
#define M_SOS 0xDA |
Definition at line 41 of file jpegSize.cpp.
Referenced by getJPEGSize().
#define NEXTBYTE | ( | ) | getc(infile) |
Definition at line 18 of file jpegSize.cpp.
Referenced by first_marker(), read_1_byte(), and read_2_bytes().
#define READ_BINARY "rb" |
Definition at line 52 of file jpegSize.cpp.
Referenced by getJPEGSize().
bool first_marker | ( | int * | res | ) |
Definition at line 149 of file jpegSize.cpp.
References M_SOI, and NEXTBYTE.
Referenced by getJPEGSize().
bool getJPEGSize | ( | const char * | filename, |
int & | width, | ||
int & | height | ||
) |
Definition at line 65 of file jpegSize.cpp.
References first_marker(), infile, M_EOI, M_SOF0, M_SOF1, M_SOF10, M_SOF11, M_SOF13, M_SOF14, M_SOF15, M_SOF2, M_SOF3, M_SOF5, M_SOF6, M_SOF7, M_SOF9, M_SOS, next_marker(), process_SOFn(), READ_BINARY, and skip_variable().
Referenced by getImageSize(), and isJpeg().
{ //open file if ((infile = fopen(filename, READ_BINARY)) == NULL) return false; //this is scan_JPEG_header (int verbose) //Parse the marker stream until SOFn is seen; int marker; //Expect SOI at start of file if (!first_marker(&marker)) { fclose(infile); return false; } /* Scan miscellaneous markers until we reach SOFn. */ for (;;) { if(!next_marker(&marker)) { fclose(infile); return false; } switch (marker) { /* Note that marker codes 0xC4, 0xC8, 0xCC are not, and must not be, * treated as SOFn. C4 in particular is actually DHT. */ case M_SOF0: /* Baseline */ case M_SOF1: /* Extended sequential, Huffman */ case M_SOF2: /* Progressive, Huffman */ case M_SOF3: /* Lossless, Huffman */ case M_SOF5: /* Differential sequential, Huffman */ case M_SOF6: /* Differential progressive, Huffman */ case M_SOF7: /* Differential lossless, Huffman */ case M_SOF9: /* Extended sequential, arithmetic */ case M_SOF10: /* Progressive, arithmetic */ case M_SOF11: /* Lossless, arithmetic */ case M_SOF13: /* Differential sequential, arithmetic */ case M_SOF14: /* Differential progressive, arithmetic */ case M_SOF15: /* Differential lossless, arithmetic */ if(!process_SOFn(width, height)) { fclose(infile); return false; } else { fclose(infile); return true; } case M_SOS: /* stop before hitting compressed data */ { fclose(infile); return false; } case M_EOI: /* in case it's a tables-only JPEG stream */ { fclose(infile); return false; } default: /* Anything else just gets skipped */ skip_variable(); /* we assume it has a parameter count... */ break; } } /* end loop */ //cout << "ERROR!\n"; return false; }
bool next_marker | ( | int * | res | ) |
Definition at line 172 of file jpegSize.cpp.
References read_1_byte().
Referenced by getJPEGSize().
{ int c; int discarded_bytes = 0; /* Find 0xFF byte; count and skip any non-FFs. */ if(!read_1_byte(&c)) return false; while (c != 0xFF) { discarded_bytes++; if(!read_1_byte(&c)) return false; } /* Get marker code byte, swallowing any duplicate FF bytes. Extra FFs * are legal as pad bytes, so don't count them in discarded_bytes. */ do { if(!read_1_byte(&c)) return false; } while (c == 0xFF); // if (discarded_bytes != 0) { cout << "Warning: garbage data found in JPEG file\n"; } *res = c; return true; }
bool process_SOFn | ( | int & | width, |
int & | height | ||
) |
Definition at line 261 of file jpegSize.cpp.
References read_1_byte(), and read_2_bytes().
Referenced by getJPEGSize().
{ unsigned int length; unsigned int image_height, image_width; int data_precision; if(!read_2_bytes(&length) || !read_1_byte(&data_precision) || !read_2_bytes(&image_height) || !read_2_bytes(&image_width) ) return false; width = (int) image_width; height = (int) image_height; return true; }
bool read_1_byte | ( | int * | res | ) |
Definition at line 202 of file jpegSize.cpp.
References NEXTBYTE.
Referenced by next_marker(), process_SOFn(), and skip_variable().
{ int c = NEXTBYTE(); if (c == EOF) return false; else { *res = c; return true; } }
bool read_2_bytes | ( | unsigned int * | res | ) |
Definition at line 216 of file jpegSize.cpp.
References NEXTBYTE.
Referenced by process_SOFn(), and skip_variable().
bool skip_variable | ( | ) |
Definition at line 237 of file jpegSize.cpp.
References read_1_byte(), and read_2_bytes().
Referenced by getJPEGSize().
{ unsigned int length; /* Get the marker parameter length count */ if(!read_2_bytes(&length)) return false; /* Length includes itself, so must be at least 2 */ if (length < 2) return false; length -= 2; /* Skip over the remaining bytes */ while (length > 0) { int tmp; if(!read_1_byte(&tmp)) return false; length--; } return false; }
FILE* infile |
Definition at line 56 of file jpegSize.cpp.
Referenced by getJPEGSize().