void PsdImage::readMetadata()
{
#ifdef DEBUG
std::cerr << "Exiv2::PsdImage::readMetadata: Reading Photoshop file " << io_->path() << "\n";
#endif
if (io_->open() != 0)
{
throw Error(9, io_->path(), strError());
}
IoCloser closer(*io_);
// Ensure that this is the correct image type
if (!isPsdType(*io_, false))
{
if (io_->error() || io_->eof()) throw Error(14);
throw Error(3, "Photoshop");
}
clearMetadata();
/*
The Photoshop header goes as follows -- all numbers are in big-endian byte order:
offset length name description
====== ======= ========= =========
0 4 bytes signature always '8BPS'
4 2 bytes version always equal to 1
6 6 bytes reserved must be zero
12 2 bytes channels number of channels in the image, including alpha channels (1 to 24)
14 4 bytes rows the height of the image in pixels
18 4 bytes columns the width of the image in pixels
22 2 bytes depth the number of bits per channel
24 2 bytes mode the color mode of the file; Supported values are: Bitmap=0; Grayscale=1; Indexed=2; RGB=3; CMYK=4; Multichannel=7; Duotone=8; Lab=9
*/
byte buf[26];
if (io_->read(buf, 26) != 26)
{
throw Error(3, "Photoshop");
}
pixelWidth_ = getLong(buf + 18, bigEndian);
pixelHeight_ = getLong(buf + 14, bigEndian);
// immediately following the image header is the color mode data section,
// the first four bytes of which specify the byte size of the whole section
if (io_->read(buf, 4) != 4)
{
throw Error(3, "Photoshop");
}
// skip it
uint32_t colorDataLength = getLong(buf, bigEndian);
if (io_->seek(colorDataLength, BasicIo::cur))
{
throw Error(3, "Photoshop");
}
// after the color data section, comes a list of resource blocks, preceeded by the total byte size
if (io_->read(buf, 4) != 4)
{
throw Error(3, "Photoshop");
}
uint32_t resourcesLength = getLong(buf, bigEndian);
while (resourcesLength > 0)
{
if (io_->read(buf, 8) != 8)
{
throw Error(3, "Photoshop");
}
// read resource type and ID
uint32_t resourceType = getLong(buf, bigEndian);
uint16_t resourceId = getShort(buf + 4, bigEndian);
if (resourceType != kPhotoshopResourceType)
{
break; // bad resource type
}
uint32_t resourceNameLength = buf[6] & ~1;
// skip the resource name, plus any padding
io_->seek(resourceNameLength, BasicIo::cur);
// read resource size
if (io_->read(buf, 4) != 4)
{
throw Error(3, "Photoshop");
}
uint32_t resourceSize = getLong(buf, bigEndian);
uint32_t curOffset = io_->tell();
processResourceBlock(resourceId, resourceSize);
resourceSize = (resourceSize + 1) & ~1; // pad to even
io_->seek(curOffset + resourceSize, BasicIo::beg);
resourcesLength -= (12 + resourceNameLength + resourceSize);
}
} // PsdImage::readMetadata
void PsdImage::doWriteMetadata(BasicIo& outIo)
{
if (!io_->isopen()) throw Error(20);
if (!outIo.isopen()) throw Error(21);
#ifdef DEBUG
std::cout << "Exiv2::PsdImage::doWriteMetadata: Writing PSD file " << io_->path() << "\n";
std::cout << "Exiv2::PsdImage::doWriteMetadata: tmp file created " << outIo.path() << "\n";
#endif
// Ensure that this is the correct image type
if (!isPsdType(*io_, true)) {
if (io_->error() || io_->eof()) throw Error(20);
throw Error(22);
}
io_->seek(0, BasicIo::beg); // rewind
DataBuf lbuf(4096);
byte buf[8];
// Get Photoshop header from original file
byte psd_head[26];
if (io_->read(psd_head, 26) != 26) throw Error(3, "Photoshop");
// Write Photoshop header data out to new PSD file
if (outIo.write(psd_head, 26) != 26) throw Error(21);
// Read colorDataLength from original PSD
if (io_->read(buf, 4) != 4) throw Error(3, "Photoshop");
uint32_t colorDataLength = getULong(buf, bigEndian);
// Write colorDataLength
ul2Data(buf, colorDataLength, bigEndian);
if (outIo.write(buf, 4) != 4) throw Error(21);
#ifdef DEBUG
std::cerr << std::dec << "colorDataLength: " << colorDataLength << "\n";
#endif
// Copy colorData
uint32_t readTotal = 0;
long toRead = 0;
while (readTotal < colorDataLength) {
toRead = static_cast<long>(colorDataLength - readTotal) < lbuf.size_
? colorDataLength - readTotal : lbuf.size_;
if (io_->read(lbuf.pData_, toRead) != toRead) throw Error(3, "Photoshop");
readTotal += toRead;
if (outIo.write(lbuf.pData_, toRead) != toRead) throw Error(21);
}
if (outIo.error()) throw Error(21);
uint32_t resLenOffset = io_->tell(); // remember for later update
// Read length of all resource blocks from original PSD
if (io_->read(buf, 4) != 4) throw Error(3, "Photoshop");
uint32_t oldResLength = getULong(buf, bigEndian);
uint32_t newResLength = 0;
// Write oldResLength (will be updated later)
ul2Data(buf, oldResLength, bigEndian);
if (outIo.write(buf, 4) != 4) throw Error(21);
#ifdef DEBUG
std::cerr << std::dec << "oldResLength: " << oldResLength << "\n";
#endif
// Iterate over original resource blocks.
// Replace or insert IPTC, EXIF and XMP
// Original resource blocks assumed to be sorted ASC
bool iptcDone = false;
bool exifDone = false;
bool xmpDone = false;
while (oldResLength > 0) {
if (io_->read(buf, 8) != 8) throw Error(3, "Photoshop");
// read resource type and ID
uint32_t resourceType = getULong(buf, bigEndian);
if (resourceType != kPhotoshopResourceType) {
break; // bad resource type
}
uint16_t resourceId = getUShort(buf + 4, bigEndian);
uint32_t resourceNameLength = buf[6];
uint32_t adjResourceNameLen = resourceNameLength & ~1;
unsigned char resourceNameFirstChar = buf[7];
// read rest of resource name, plus any padding
DataBuf resName(256);
if ( io_->read(resName.pData_, adjResourceNameLen)
!= static_cast<long>(adjResourceNameLen)) throw Error(3, "Photoshop");
// read resource size (actual length w/o padding!)
if (io_->read(buf, 4) != 4) throw Error(3, "Photoshop");
uint32_t resourceSize = getULong(buf, bigEndian);
uint32_t curOffset = io_->tell();
// Write IPTC_NAA resource block
if ( resourceId == kPhotoshopResourceID_IPTC_NAA
|| (resourceId > kPhotoshopResourceID_IPTC_NAA && iptcDone == false)) {
newResLength += writeIptcData(iptcData_, outIo);
resourceSize = (resourceSize + 1) & ~1; // adjust for padding
iptcDone = true;
}
// Write ExifInfo resource block
else if ( resourceId == kPhotoshopResourceID_ExifInfo
|| (resourceId > kPhotoshopResourceID_ExifInfo && exifDone == false)) {
newResLength += writeExifData(exifData_, outIo);
resourceSize = (resourceSize + 1) & ~1; // adjust for padding
exifDone = true;
}
// Write XMPpacket resource block
else if ( resourceId == kPhotoshopResourceID_XMPPacket
|| (resourceId > kPhotoshopResourceID_XMPPacket && xmpDone == false)) {
newResLength += writeXmpData(xmpData_, outIo);
resourceSize = (resourceSize + 1) & ~1; // adjust for padding
xmpDone = true;
}
// Copy all other resource blocks
if ( resourceId != kPhotoshopResourceID_IPTC_NAA
&& resourceId != kPhotoshopResourceID_ExifInfo
&& resourceId != kPhotoshopResourceID_XMPPacket) {
#ifdef DEBUG
std::cerr << std::hex << "copy : resourceId: " << resourceId << "\n";
std::cerr << std::dec;
#endif
// Copy resource block to new PSD file
ul2Data(buf, kPhotoshopResourceType, bigEndian);
if (outIo.write(buf, 4) != 4) throw Error(21);
us2Data(buf, resourceId, bigEndian);
if (outIo.write(buf, 2) != 2) throw Error(21);
// Write resource name as Pascal string
buf[0] = resourceNameLength & 0x000f;
if (outIo.write(buf, 1) != 1) throw Error(21);
buf[0] = resourceNameFirstChar;
if (outIo.write(buf, 1) != 1) throw Error(21);
if ( outIo.write(resName.pData_, adjResourceNameLen)
!= static_cast<long>(adjResourceNameLen)) throw Error(21);
ul2Data(buf, resourceSize, bigEndian);
if (outIo.write(buf, 4) != 4) throw Error(21);
readTotal = 0;
toRead = 0;
resourceSize = (resourceSize + 1) & ~1; // pad to even
while (readTotal < resourceSize) {
toRead = static_cast<long>(resourceSize - readTotal) < lbuf.size_
? resourceSize - readTotal : lbuf.size_;
if (io_->read(lbuf.pData_, toRead) != toRead) {
throw Error(3, "Photoshop");
}
readTotal += toRead;
if (outIo.write(lbuf.pData_, toRead) != toRead) throw Error(21);
}
if (outIo.error()) throw Error(21);
newResLength += resourceSize + adjResourceNameLen + 12;
}
io_->seek(curOffset + resourceSize, BasicIo::beg);
oldResLength -= (12 + adjResourceNameLen + resourceSize);
}
// Append IPTC_NAA resource block, if not yet written
if (iptcDone == false) {
newResLength += writeIptcData(iptcData_, outIo);
iptcDone = true;
}
// Append ExifInfo resource block, if not yet written
if (exifDone == false) {
newResLength += writeExifData(exifData_, outIo);
exifDone = true;
}
// Append XmpPacket resource block, if not yet written
if (xmpDone == false) {
newResLength += writeXmpData(xmpData_, outIo);
xmpDone = true;
}
// Copy remaining data
long readSize = 0;
while ((readSize=io_->read(lbuf.pData_, lbuf.size_))) {
if (outIo.write(lbuf.pData_, readSize) != readSize) throw Error(21);
}
if (outIo.error()) throw Error(21);
// Update length of resources
#ifdef DEBUG
std::cerr << "newResLength: " << newResLength << "\n";
#endif
outIo.seek(resLenOffset, BasicIo::beg);
ul2Data(buf, newResLength, bigEndian);
if (outIo.write(buf, 4) != 4) throw Error(21);
} // PsdImage::doWriteMetadata
