From c91847d549cc1c30eb15504a15ea9a6d5aa48165 Mon Sep 17 00:00:00 2001 From: "chirs241097@gmail.com" Date: Sun, 12 Jan 2014 14:43:14 +0000 Subject: --- hge/CxImage/ximaexif.cpp | 877 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 877 insertions(+) create mode 100644 hge/CxImage/ximaexif.cpp (limited to 'hge/CxImage/ximaexif.cpp') diff --git a/hge/CxImage/ximaexif.cpp b/hge/CxImage/ximaexif.cpp new file mode 100644 index 0000000..f880d72 --- /dev/null +++ b/hge/CxImage/ximaexif.cpp @@ -0,0 +1,877 @@ +/* + * File: ximaexif.cpp + * Purpose: EXIF reader + * 18/Aug/2002 Davide Pizzolato - www.xdp.it + * CxImage version 7.0.0 31/Dec/2010 + * based on jhead-1.8 by Matthias Wandel + */ + +#include "ximajpg.h" + +#if CXIMAGEJPG_SUPPORT_EXIF + +//////////////////////////////////////////////////////////////////////////////// +CxImageJPG::CxExifInfo::CxExifInfo(EXIFINFO* info) +{ + if (info) { + m_exifinfo = info; + freeinfo = false; + } else { + m_exifinfo = new EXIFINFO; + memset(m_exifinfo,0,sizeof(EXIFINFO)); + freeinfo = true; + } + + m_szLastError[0]='\0'; + ExifImageWidth = MotorolaOrder = 0; + SectionsRead=0; + memset(&Sections, 0, MAX_SECTIONS * sizeof(Section_t)); +} +//////////////////////////////////////////////////////////////////////////////// +CxImageJPG::CxExifInfo::~CxExifInfo() +{ + for(int32_t i=0;iGetC(); + + if (a != 0xff || hFile->GetC() != M_SOI){ + return FALSE; + } + + for(;;){ + int32_t itemlen; + int32_t marker = 0; + int32_t ll,lh, got; + uint8_t * Data; + + if (SectionsRead >= MAX_SECTIONS){ + strcpy(m_szLastError,"Too many sections in jpg file"); + return false; + } + + for (a=0;a<7;a++){ + marker = hFile->GetC(); + if (marker != 0xff) break; + + if (a >= 6){ + printf("too many padding bytes\n"); + return false; + } + } + + if (marker == 0xff){ + // 0xff is legal padding, but if we get that many, something's wrong. + strcpy(m_szLastError,"too many padding bytes!"); + return false; + } + + Sections[SectionsRead].Type = marker; + + // Read the length of the section. + lh = hFile->GetC(); + ll = hFile->GetC(); + + itemlen = (lh << 8) | ll; + + if (itemlen < 2){ + strcpy(m_szLastError,"invalid marker"); + return false; + } + + Sections[SectionsRead].Size = itemlen; + + Data = (uint8_t *)malloc(itemlen); + if (Data == NULL){ + strcpy(m_szLastError,"Could not allocate memory"); + return false; + } + Sections[SectionsRead].Data = Data; + + // Store first two pre-read bytes. + Data[0] = (uint8_t)lh; + Data[1] = (uint8_t)ll; + + got = hFile->Read(Data+2, 1, itemlen-2); // Read the whole section. + if (got != itemlen-2){ + strcpy(m_szLastError,"Premature end of file?"); + return false; + } + SectionsRead += 1; + + switch(marker){ + + case M_SOS: // stop before hitting compressed data + // If reading entire image is requested, read the rest of the data. + if (nReadMode & EXIF_READ_IMAGE){ + int32_t cp, ep, size; + // Determine how much file is left. + cp = hFile->Tell(); + hFile->Seek(0, SEEK_END); + ep = hFile->Tell(); + hFile->Seek(cp, SEEK_SET); + + size = ep-cp; + Data = (uint8_t *)malloc(size); + if (Data == NULL){ + strcpy(m_szLastError,"could not allocate data for entire image"); + return false; + } + + got = hFile->Read(Data, 1, size); + if (got != size){ + strcpy(m_szLastError,"could not read the rest of the image"); + return false; + } + + Sections[SectionsRead].Data = Data; + Sections[SectionsRead].Size = size; + Sections[SectionsRead].Type = PSEUDO_IMAGE_MARKER; + SectionsRead ++; + } + return true; + + case M_EOI: // in case it's a tables-only JPEG stream + printf("No image in jpeg!\n"); + return FALSE; + + case M_COM: // Comment section + if (HaveCom || ((nReadMode & EXIF_READ_EXIF) == 0)){ + // Discard this section. + free(Sections[--SectionsRead].Data); + Sections[SectionsRead].Data=0; + }else{ + process_COM(Data, itemlen); + HaveCom = TRUE; + } + break; + + case M_JFIF: + // Regular jpegs always have this tag, exif images have the exif + // marker instead, althogh ACDsee will write images with both markers. + // this program will re-create this marker on absence of exif marker. + // hence no need to keep the copy from the file. + free(Sections[--SectionsRead].Data); + Sections[SectionsRead].Data=0; + break; + + case M_EXIF: + // Seen files from some 'U-lead' software with Vivitar scanner + // that uses marker 31 for non exif stuff. Thus make sure + // it says 'Exif' in the section before treating it as exif. + if ((nReadMode & EXIF_READ_EXIF) && memcmp(Data+2, "Exif", 4) == 0){ + m_exifinfo->IsExif = process_EXIF((uint8_t *)Data+2, itemlen); + }else{ + // Discard this section. + free(Sections[--SectionsRead].Data); + Sections[SectionsRead].Data=0; + } + break; + + case M_SOF0: + case M_SOF1: + case M_SOF2: + case M_SOF3: + case M_SOF5: + case M_SOF6: + case M_SOF7: + case M_SOF9: + case M_SOF10: + case M_SOF11: + case M_SOF13: + case M_SOF14: + case M_SOF15: + process_SOFn(Data, marker); + break; + default: + // Skip any other sections. + //if (ShowTags) printf("Jpeg section marker 0x%02x size %d\n",marker, itemlen); + break; + } + } + return true; +} +//////////////////////////////////////////////////////////////////////////////// +/*-------------------------------------------------------------------------- + Process a EXIF marker + Describes all the drivel that most digital cameras include... +--------------------------------------------------------------------------*/ +bool CxImageJPG::CxExifInfo::process_EXIF(uint8_t * CharBuf, uint32_t length) +{ + m_exifinfo->FlashUsed = 0; + /* If it's from a digicam, and it used flash, it says so. */ + m_exifinfo->Comments[0] = '\0'; /* Initial value - null string */ + + ExifImageWidth = 0; + + { /* Check the EXIF header component */ + static const uint8_t ExifHeader[] = "Exif\0\0"; + if (memcmp(CharBuf+0, ExifHeader,6)){ + strcpy(m_szLastError,"Incorrect Exif header"); + return false; + } + } + + if (memcmp(CharBuf+6,"II",2) == 0){ + MotorolaOrder = 0; + }else{ + if (memcmp(CharBuf+6,"MM",2) == 0){ + MotorolaOrder = 1; + }else{ + strcpy(m_szLastError,"Invalid Exif alignment marker."); + return false; + } + } + + /* Check the next two values for correctness. */ + if (Get16u(CharBuf+8) != 0x2a){ + strcpy(m_szLastError,"Invalid Exif start (1)"); + return false; + } + + int32_t FirstOffset = Get32u(CharBuf+10); + /* + if (FirstOffset < 8 || FirstOffset > 16){ + // I used to ensure this was set to 8 (website I used indicated its 8) + // but PENTAX Optio 230 has it set differently, and uses it as offset. (Sept 11 2002) + strcpy(m_szLastError,"Suspicious offset of first IFD value"); + return false; + }*/ + + uint8_t * LastExifRefd = CharBuf; + + /* First directory starts 16 bytes in. Offsets start at 8 bytes in. */ + if (!ProcessExifDir(CharBuf+14, CharBuf+6, length-6, m_exifinfo, &LastExifRefd)) + return false; + + /* give a chance for a second directory */ + if (FirstOffset > 8) { + if (!ProcessExifDir(CharBuf+14+FirstOffset-8, CharBuf+6, length-6, m_exifinfo, &LastExifRefd)) + return false; + } + + /* This is how far the interesting (non thumbnail) part of the exif went. */ + // int32_t ExifSettingsLength = LastExifRefd - CharBuf; + + /* Compute the CCD width, in milimeters. */ + if (m_exifinfo->FocalplaneXRes != 0){ + m_exifinfo->CCDWidth = (float)(ExifImageWidth * m_exifinfo->FocalplaneUnits / m_exifinfo->FocalplaneXRes); + } + + return true; +} +//-------------------------------------------------------------------------- +// Get 16 bits motorola order (always) for jpeg header stuff. +//-------------------------------------------------------------------------- +int32_t CxImageJPG::CxExifInfo::Get16m(void * Short) +{ + return (((uint8_t *)Short)[0] << 8) | ((uint8_t *)Short)[1]; +} +//////////////////////////////////////////////////////////////////////////////// +/*-------------------------------------------------------------------------- + Convert a 16 bit unsigned value from file's native byte order +--------------------------------------------------------------------------*/ +int32_t CxImageJPG::CxExifInfo::Get16u(void * Short) +{ + if (MotorolaOrder){ + return (((uint8_t *)Short)[0] << 8) | ((uint8_t *)Short)[1]; + }else{ + return (((uint8_t *)Short)[1] << 8) | ((uint8_t *)Short)[0]; + } +} +//////////////////////////////////////////////////////////////////////////////// +/*-------------------------------------------------------------------------- + Convert a 32 bit signed value from file's native byte order +--------------------------------------------------------------------------*/ +int32_t CxImageJPG::CxExifInfo::Get32s(void * Long) +{ + if (MotorolaOrder){ + return ((( char *)Long)[0] << 24) | (((uint8_t *)Long)[1] << 16) + | (((uint8_t *)Long)[2] << 8 ) | (((uint8_t *)Long)[3] << 0 ); + }else{ + return ((( char *)Long)[3] << 24) | (((uint8_t *)Long)[2] << 16) + | (((uint8_t *)Long)[1] << 8 ) | (((uint8_t *)Long)[0] << 0 ); + } +} +//////////////////////////////////////////////////////////////////////////////// +/*-------------------------------------------------------------------------- + Convert a 32 bit unsigned value from file's native byte order +--------------------------------------------------------------------------*/ +uint32_t CxImageJPG::CxExifInfo::Get32u(void * Long) +{ + return (uint32_t)Get32s(Long) & 0xffffffff; +} +//////////////////////////////////////////////////////////////////////////////// + +/* Describes format descriptor */ +static const int32_t BytesPerFormat[] = {0,1,1,2,4,8,1,1,2,4,8,4,8}; +#define NUM_FORMATS 12 + +#define FMT_BYTE 1 +#define FMT_STRING 2 +#define FMT_USHORT 3 +#define FMT_ULONG 4 +#define FMT_URATIONAL 5 +#define FMT_SBYTE 6 +#define FMT_UNDEFINED 7 +#define FMT_SSHORT 8 +#define FMT_SLONG 9 +#define FMT_SRATIONAL 10 +#define FMT_SINGLE 11 +#define FMT_DOUBLE 12 + +/* Describes tag values */ + +#define TAG_EXIF_VERSION 0x9000 +#define TAG_EXIF_OFFSET 0x8769 +#define TAG_INTEROP_OFFSET 0xa005 + +#define TAG_MAKE 0x010F +#define TAG_MODEL 0x0110 + +#define TAG_ORIENTATION 0x0112 +#define TAG_XRESOLUTION 0x011A +#define TAG_YRESOLUTION 0x011B +#define TAG_RESOLUTIONUNIT 0x0128 + +#define TAG_EXPOSURETIME 0x829A +#define TAG_FNUMBER 0x829D + +#define TAG_SHUTTERSPEED 0x9201 +#define TAG_APERTURE 0x9202 +#define TAG_BRIGHTNESS 0x9203 +#define TAG_MAXAPERTURE 0x9205 +#define TAG_FOCALLENGTH 0x920A + +#define TAG_DATETIME_ORIGINAL 0x9003 +#define TAG_USERCOMMENT 0x9286 + +#define TAG_SUBJECT_DISTANCE 0x9206 +#define TAG_FLASH 0x9209 + +#define TAG_FOCALPLANEXRES 0xa20E +#define TAG_FOCALPLANEYRES 0xa20F +#define TAG_FOCALPLANEUNITS 0xa210 +#define TAG_EXIF_IMAGEWIDTH 0xA002 +#define TAG_EXIF_IMAGELENGTH 0xA003 + +/* the following is added 05-jan-2001 vcs */ +#define TAG_EXPOSURE_BIAS 0x9204 +#define TAG_WHITEBALANCE 0x9208 +#define TAG_METERING_MODE 0x9207 +#define TAG_EXPOSURE_PROGRAM 0x8822 +#define TAG_ISO_EQUIVALENT 0x8827 +#define TAG_COMPRESSION_LEVEL 0x9102 + +#define TAG_THUMBNAIL_OFFSET 0x0201 +#define TAG_THUMBNAIL_LENGTH 0x0202 + + +/*-------------------------------------------------------------------------- + Process one of the nested EXIF directories. +--------------------------------------------------------------------------*/ +bool CxImageJPG::CxExifInfo::ProcessExifDir(uint8_t * DirStart, uint8_t * OffsetBase, unsigned ExifLength, + EXIFINFO * const m_exifinfo, uint8_t ** const LastExifRefdP, int32_t NestingLevel) +{ + int32_t de; + int32_t a; + int32_t NumDirEntries; + unsigned ThumbnailOffset = 0; + unsigned ThumbnailSize = 0; + + if (NestingLevel > 4){ + strcpy(m_szLastError,"Maximum directory nesting exceeded (corrupt exif header)"); + return false; + } + + NumDirEntries = Get16u(DirStart); + + if ((DirStart+2+NumDirEntries*12) > (OffsetBase+ExifLength)){ + strcpy(m_szLastError,"Illegally sized directory"); + return false; + } + + for (de=0;de= NUM_FORMATS) { + /* (-1) catches illegal zero case as unsigned underflows to positive large */ + strcpy(m_szLastError,"Illegal format code in EXIF dir"); + return false; + } + + ByteCount = Components * BytesPerFormat[Format]; + + if (ByteCount > 4){ + unsigned OffsetVal; + OffsetVal = Get32u(DirEntry+8); + /* If its bigger than 4 bytes, the dir entry contains an offset.*/ + if (OffsetVal+ByteCount > ExifLength){ + /* Bogus pointer offset and / or bytecount value */ + strcpy(m_szLastError,"Illegal pointer offset value in EXIF."); + return false; + } + ValuePtr = OffsetBase+OffsetVal; + }else{ + /* 4 bytes or less and value is in the dir entry itself */ + ValuePtr = DirEntry+8; + } + + if (*LastExifRefdP < ValuePtr+ByteCount){ + /* Keep track of last byte in the exif header that was + actually referenced. That way, we know where the + discardable thumbnail data begins. + */ + *LastExifRefdP = ValuePtr+ByteCount; + } + + /* Extract useful components of tag */ + switch(Tag){ + + case TAG_MAKE: + strncpy(m_exifinfo->CameraMake, (char*)ValuePtr, 31); + break; + + case TAG_MODEL: + strncpy(m_exifinfo->CameraModel, (char*)ValuePtr, 39); + break; + + case TAG_EXIF_VERSION: + strncpy(m_exifinfo->Version,(char*)ValuePtr, 4); + break; + + case TAG_DATETIME_ORIGINAL: + strncpy(m_exifinfo->DateTime, (char*)ValuePtr, 19); + break; + + case TAG_USERCOMMENT: + // Olympus has this padded with trailing spaces. Remove these first. + for (a=ByteCount;;){ + a--; + if (((char*)ValuePtr)[a] == ' '){ + ((char*)ValuePtr)[a] = '\0'; + }else{ + break; + } + if (a == 0) break; + } + + /* Copy the comment */ + if (memcmp(ValuePtr, "ASCII",5) == 0){ + for (a=5;a<10;a++){ + char c; + c = ((char*)ValuePtr)[a]; + if (c != '\0' && c != ' '){ + strncpy(m_exifinfo->Comments, (char*)ValuePtr+a, 199); + break; + } + } + + }else{ + strncpy(m_exifinfo->Comments, (char*)ValuePtr, 199); + } + break; + + case TAG_FNUMBER: + /* Simplest way of expressing aperture, so I trust it the most. + (overwrite previously computd value if there is one) + */ + m_exifinfo->ApertureFNumber = (float)ConvertAnyFormat(ValuePtr, Format); + break; + + case TAG_APERTURE: + case TAG_MAXAPERTURE: + /* More relevant info always comes earlier, so only + use this field if we don't have appropriate aperture + information yet. + */ + if (m_exifinfo->ApertureFNumber == 0){ + m_exifinfo->ApertureFNumber = (float)exp(ConvertAnyFormat(ValuePtr, Format)*log(2.0f)*0.5); + } + break; + + case TAG_BRIGHTNESS: + m_exifinfo->Brightness = (float)ConvertAnyFormat(ValuePtr, Format); + break; + + case TAG_FOCALLENGTH: + /* Nice digital cameras actually save the focal length + as a function of how farthey are zoomed in. + */ + + m_exifinfo->FocalLength = (float)ConvertAnyFormat(ValuePtr, Format); + break; + + case TAG_SUBJECT_DISTANCE: + /* Inidcates the distacne the autofocus camera is focused to. + Tends to be less accurate as distance increases. + */ + m_exifinfo->Distance = (float)ConvertAnyFormat(ValuePtr, Format); + break; + + case TAG_EXPOSURETIME: + /* Simplest way of expressing exposure time, so I + trust it most. (overwrite previously computd value + if there is one) + */ + m_exifinfo->ExposureTime = + (float)ConvertAnyFormat(ValuePtr, Format); + break; + + case TAG_SHUTTERSPEED: + /* More complicated way of expressing exposure time, + so only use this value if we don't already have it + from somewhere else. + */ + if (m_exifinfo->ExposureTime == 0){ + m_exifinfo->ExposureTime = (float) + (1/exp(ConvertAnyFormat(ValuePtr, Format)*log(2.0f))); + } + break; + + case TAG_FLASH: + if ((int32_t)ConvertAnyFormat(ValuePtr, Format) & 7){ + m_exifinfo->FlashUsed = 1; + }else{ + m_exifinfo->FlashUsed = 0; + } + break; + + case TAG_ORIENTATION: + m_exifinfo->Orientation = (int32_t)ConvertAnyFormat(ValuePtr, Format); + if (m_exifinfo->Orientation < 1 || m_exifinfo->Orientation > 8){ + strcpy(m_szLastError,"Undefined rotation value"); + m_exifinfo->Orientation = 0; + } + break; + + case TAG_EXIF_IMAGELENGTH: + case TAG_EXIF_IMAGEWIDTH: + /* Use largest of height and width to deal with images + that have been rotated to portrait format. + */ + a = (int32_t)ConvertAnyFormat(ValuePtr, Format); + if (ExifImageWidth < a) ExifImageWidth = a; + break; + + case TAG_FOCALPLANEXRES: + m_exifinfo->FocalplaneXRes = (float)ConvertAnyFormat(ValuePtr, Format); + break; + + case TAG_FOCALPLANEYRES: + m_exifinfo->FocalplaneYRes = (float)ConvertAnyFormat(ValuePtr, Format); + break; + + case TAG_RESOLUTIONUNIT: + switch((int32_t)ConvertAnyFormat(ValuePtr, Format)){ + case 1: m_exifinfo->ResolutionUnit = 1.0f; break; /* 1 inch */ + case 2: m_exifinfo->ResolutionUnit = 1.0f; break; + case 3: m_exifinfo->ResolutionUnit = 0.3937007874f; break; /* 1 centimeter*/ + case 4: m_exifinfo->ResolutionUnit = 0.03937007874f; break; /* 1 millimeter*/ + case 5: m_exifinfo->ResolutionUnit = 0.00003937007874f; /* 1 micrometer*/ + } + break; + + case TAG_FOCALPLANEUNITS: + switch((int32_t)ConvertAnyFormat(ValuePtr, Format)){ + case 1: m_exifinfo->FocalplaneUnits = 1.0f; break; /* 1 inch */ + case 2: m_exifinfo->FocalplaneUnits = 1.0f; break; + case 3: m_exifinfo->FocalplaneUnits = 0.3937007874f; break; /* 1 centimeter*/ + case 4: m_exifinfo->FocalplaneUnits = 0.03937007874f; break; /* 1 millimeter*/ + case 5: m_exifinfo->FocalplaneUnits = 0.00003937007874f; /* 1 micrometer*/ + } + break; + + // Remaining cases contributed by: Volker C. Schoech + + case TAG_EXPOSURE_BIAS: + m_exifinfo->ExposureBias = (float) ConvertAnyFormat(ValuePtr, Format); + break; + + case TAG_WHITEBALANCE: + m_exifinfo->Whitebalance = (int32_t)ConvertAnyFormat(ValuePtr, Format); + break; + + case TAG_METERING_MODE: + m_exifinfo->MeteringMode = (int32_t)ConvertAnyFormat(ValuePtr, Format); + break; + + case TAG_EXPOSURE_PROGRAM: + m_exifinfo->ExposureProgram = (int32_t)ConvertAnyFormat(ValuePtr, Format); + break; + + case TAG_ISO_EQUIVALENT: + m_exifinfo->ISOequivalent = (int32_t)ConvertAnyFormat(ValuePtr, Format); + if ( m_exifinfo->ISOequivalent < 50 ) m_exifinfo->ISOequivalent *= 200; + break; + + case TAG_COMPRESSION_LEVEL: + m_exifinfo->CompressionLevel = (int32_t)ConvertAnyFormat(ValuePtr, Format); + break; + + case TAG_XRESOLUTION: + m_exifinfo->Xresolution = (float)ConvertAnyFormat(ValuePtr, Format); + break; + case TAG_YRESOLUTION: + m_exifinfo->Yresolution = (float)ConvertAnyFormat(ValuePtr, Format); + break; + + case TAG_THUMBNAIL_OFFSET: + ThumbnailOffset = (unsigned)ConvertAnyFormat(ValuePtr, Format); + break; + + case TAG_THUMBNAIL_LENGTH: + ThumbnailSize = (unsigned)ConvertAnyFormat(ValuePtr, Format); + break; + + } + + if (Tag == TAG_EXIF_OFFSET || Tag == TAG_INTEROP_OFFSET){ + uint8_t * SubdirStart; + unsigned Offset = Get32u(ValuePtr); + if (Offset>8){ + SubdirStart = OffsetBase + Offset; + if (SubdirStart < OffsetBase || + SubdirStart > OffsetBase+ExifLength){ + strcpy(m_szLastError,"Illegal subdirectory link"); + return false; + } + ProcessExifDir(SubdirStart, OffsetBase, ExifLength, m_exifinfo, LastExifRefdP, NestingLevel+1); + } + continue; + } + } + + + { + /* In addition to linking to subdirectories via exif tags, + there's also a potential link to another directory at the end + of each directory. This has got to be the result of a + committee! + */ + uint8_t * SubdirStart; + unsigned Offset; + Offset = Get16u(DirStart+2+12*NumDirEntries); + if (Offset){ + SubdirStart = OffsetBase + Offset; + if (SubdirStart < OffsetBase + || SubdirStart > OffsetBase+ExifLength){ + strcpy(m_szLastError,"Illegal subdirectory link"); + return false; + } + ProcessExifDir(SubdirStart, OffsetBase, ExifLength, m_exifinfo, LastExifRefdP, NestingLevel+1); + } + } + + + if (ThumbnailSize && ThumbnailOffset){ + if (ThumbnailSize + ThumbnailOffset <= ExifLength){ + /* The thumbnail pointer appears to be valid. Store it. */ + m_exifinfo->ThumbnailPointer = OffsetBase + ThumbnailOffset; + m_exifinfo->ThumbnailSize = ThumbnailSize; + } + } + + return true; +} +//////////////////////////////////////////////////////////////////////////////// +/*-------------------------------------------------------------------------- + Evaluate number, be it int32_t, rational, or float from directory. +--------------------------------------------------------------------------*/ +double CxImageJPG::CxExifInfo::ConvertAnyFormat(void * ValuePtr, int32_t Format) +{ + double Value; + Value = 0; + + switch(Format){ + case FMT_SBYTE: Value = *(signed char *)ValuePtr; break; + case FMT_BYTE: Value = *(uint8_t *)ValuePtr; break; + + case FMT_USHORT: Value = Get16u(ValuePtr); break; + case FMT_ULONG: Value = Get32u(ValuePtr); break; + + case FMT_URATIONAL: + case FMT_SRATIONAL: + { + int32_t Num,Den; + Num = Get32s(ValuePtr); + Den = Get32s(4+(char *)ValuePtr); + if (Den == 0){ + Value = 0; + }else{ + Value = (double)Num/Den; + } + break; + } + + case FMT_SSHORT: Value = (int16_t)Get16u(ValuePtr); break; + case FMT_SLONG: Value = Get32s(ValuePtr); break; + + /* Not sure if this is correct (never seen float used in Exif format) + */ + case FMT_SINGLE: Value = (double)*(float *)ValuePtr; break; + case FMT_DOUBLE: Value = *(double *)ValuePtr; break; + } + return Value; +} +//////////////////////////////////////////////////////////////////////////////// +void CxImageJPG::CxExifInfo::process_COM (const uint8_t * Data, int32_t length) +{ + int32_t ch; + char Comment[MAX_COMMENT+1]; + int32_t nch; + int32_t a; + + nch = 0; + + if (length > MAX_COMMENT) length = MAX_COMMENT; // Truncate if it won't fit in our structure. + + for (a=2;aComments,Comment); +} +//////////////////////////////////////////////////////////////////////////////// +void CxImageJPG::CxExifInfo::process_SOFn (const uint8_t * Data, int32_t marker) +{ + int32_t data_precision, num_components; + + data_precision = Data[2]; + m_exifinfo->Height = Get16m((void*)(Data+3)); + m_exifinfo->Width = Get16m((void*)(Data+5)); + num_components = Data[7]; + + if (num_components == 3){ + m_exifinfo->IsColor = 1; + }else{ + m_exifinfo->IsColor = 0; + } + + m_exifinfo->Process = marker; + + //if (ShowTags) printf("JPEG image is %uw * %uh, %d color components, %d bits per sample\n", + // ImageInfo.Width, ImageInfo.Height, num_components, data_precision); +} +//////////////////////////////////////////////////////////////////////////////// +/** + * this will work only on a CxImageJPG object, if the image originally has valid EXIF data + \verbatim + CxImageJPG jpg; + CxIOFile in,out; + in.Open("D:\\exif_in.jpg","rb"); + out.Open("D:\\exif_out.jpg","w+b"); + jpg.Decode(&in); + if (jpg.IsValid()){ + jpg.RotateLeft(); + jpg.Encode(&out); + } + \endverbatim +*/ +bool CxImageJPG::CxExifInfo::EncodeExif(CxFile * hFile) +{ + int32_t a; + + if (FindSection(M_SOS)==NULL){ + strcpy(m_szLastError,"Can't write exif : didn't read all"); + return false; + } + + // Initial static jpeg marker. + hFile->PutC(0xff); + hFile->PutC(0xd8); + + if (Sections[0].Type != M_EXIF && Sections[0].Type != M_JFIF){ + // The image must start with an exif or jfif marker. If we threw those away, create one. + static uint8_t JfifHead[18] = { + 0xff, M_JFIF, + 0x00, 0x10, 'J' , 'F' , 'I' , 'F' , 0x00, 0x01, + 0x01, 0x01, 0x01, 0x2C, 0x01, 0x2C, 0x00, 0x00 + }; + hFile->Write(JfifHead, 18, 1); + } + + // Write all the misc sections + for (a=0;aPutC(0xff); + hFile->PutC((uint8_t)(Sections[a].Type)); + hFile->Write(Sections[a].Data, Sections[a].Size, 1); + } + + // Write the remaining image data. + hFile->Write(Sections[a].Data, Sections[a].Size, 1); + + return true; +} +//////////////////////////////////////////////////////////////////////////////// +void CxImageJPG::CxExifInfo::DiscardAllButExif() +{ + Section_t ExifKeeper; + Section_t CommentKeeper; + int32_t a; + + memset(&ExifKeeper, 0, sizeof(ExifKeeper)); + memset(&CommentKeeper, 0, sizeof(ExifKeeper)); + + for (a=0;a