Comments on: Using QMeta to extract Exif data in your Qt applications

By: Mark Johnson

Mark Johnson — Fri, 09 Mar 2012 18:08:56 +0000

In case anybody is interested, I have extended the ExifData class to support GPSLatitude/Longitude/TimeStamp/DateStamp with correct return values from the Rational, where by the DateStamp is is only replace by the ISO formatting (YYY-MM-TT)

add to exif_data.h;

double ToDegrees();
QString ToTimeStamp();
QString ToDateStampISO();

add to exif_data.cc;

double ExifData::ToDegrees()
{
QList ar_result;
qint32 i;
for (i=0;i {
double numerator = static_cast(mid(i,4).toHex().toUInt(NULL, 16));
double denominator = static_cast(mid(i+4,4).toHex().toUInt(NULL, 16));
ar_result.append(numerator/denominator);
}
return ar_result[0]+(ar_result[1]/60)+(ar_result[2]/3600);
}
QString ExifData::ToTimeStamp()
{
qint32 i;
QString s_result=”";
double d_result=0;
for (i=0;i {
double numerator = static_cast(mid(i,4).toHex().toUInt(NULL, 16));
double denominator = static_cast(mid(i+4,4).toHex().toUInt(NULL, 16));
d_result=numerator/denominator;
if (s_result != “”)
s_result+=”:”;
s_result+=QString::number(d_result);
}
return s_result;
}
QString ExifData::ToDateStampISO()
{
return QString(data()).replace(“:”, “-”);
}

By: fabrice

fabrice — Tue, 01 Nov 2011 14:02:35 +0000

I find an error in exif.cpp :
———————————

if(data->mid(6,2) == “II”){ // Exif section in Intel order
//qDebug() MotorolaOrder = 0;
}else{
if(data->mid(6,2) == “II”){ // Exif section in Motorola order
//qDebug() ————————————–
is better with ‘MM’ for Motorola :
—————————————
if(data->mid(6,2) == “II”){ // Exif section in Intel order
//qDebug() MotorolaOrder = 0;
}else{
if(data->mid(6,2) == “MM”){ // Exif section in Motorola order
//qDebug()

—————————————

Fabrice

contact@opendent.fr

By: julien

julien — Mon, 17 Oct 2011 13:55:04 +0000

I find alone. Thanks for your work.

By: julien

julien — Mon, 17 Oct 2011 12:44:07 +0000

hello.
I want toi use your library, under QT4 on Debian Squeeze with QT Creator. I’ve download it, mais I don’t now how to add it in project ? Can you help me ?

By: Hien

Hien — Sun, 13 Feb 2011 05:51:45 +0000

I followed the instructions on the README and it seems to have installed it there by default. I am really new at this, but is qmeta.so the compiled library? It is in my /usr/local/lib directory.

By: Olli Wang

Olli Wang — Sun, 13 Feb 2011 05:43:11 +0000

You need to tell QT the location of your compiled qmeta library. It seems that you installed it to the `/usr/local/lib` directory instead of the normal `/usr/lib` directory.

By: Hien

Hien — Sun, 13 Feb 2011 05:15:27 +0000

Hi Olli,

This is the error message that I am getting from qt while running the program
error while loading shared libraries: libqmeta.so: cannot open shared object file: No such file or directory.

These are the important bits in my .pro file
LIBS += -lhighgui \
-lm \
-lcv \
-lhighgui \
-lcvaux \
-lqitty \
-lqmeta

INCLUDEPATH += /usr/local/include/opencv -L /usr/local/lib \
/usr/local/include/qitty -L /usr/local/lib \
/usr/local/include/qmeta -L /usr/local/lib

Do you know why I am getting this error message? I compiled and installed both qitty and qmeta without error.

By: Olli Wang

Olli Wang — Sun, 13 Feb 2011 05:03:55 +0000

Hi, I think you need to add something like the following code to your QT’s `pro` file. However, the following code is used under Unix environment.

unix { INCLUDEPATH *= /usr/include LIBS += -lqmeta }

You are required to compile and install the qmeta library at first.

By: FalseCAM

FalseCAM — Sat, 12 Feb 2011 10:40:13 +0000

Hello,
can you write a qmeta.pro file (QT-Project file) please.
I have some problems to include this library into my project.

By: sdecorme

sdecorme — Wed, 14 Jul 2010 08:09:29 +0000

Actually my basic photo have no metadata so I’ve to add them. It seem to be more difficult then modify it.
Thanks.