//some poco stuff
HTTPStreamFactory::registerFactory();
//specify out url and open stream
URI uri("[http://www.coolhunting.com/images/funky2.jpg");](http://www.coolhunting.com/images/funky2.jpg");)
std::auto_ptr<std::istream> pStr(URIStreamOpener::defaultOpener().open(uri));
//create a file to save the stream to
ofstream myfile;
myfile.open(ofToDataPath("thumb.jpg").c_str());
//copy stream to file
StreamCopier::copyStream(*pStr.get(), myfile);
myfile.close();
//load into an ofImage!
img.loadImage(ofToDataPath("thumb.jpg"));
I am looking for a way to do essentially this, but without saving the image as a file to the filesystem. I saw the FreeImage_LoadFromHandle function in the FreeImage documentation, but I’m still unclear on how to use it. Zach mentioned that he had some code he could share. That would be great. My end goal would be to have something like:
Looks like the poco copyToString is the way to go.
string str;
StreamCopier::copyToString(*pStr.get(), str);
int bytesToRead = str.size();
char buff[bytesToRead];
memset(buff, 0, bytesToRead);
for(int i = 0; i < bytesToRead; i++){
buff[i] = str[i];
}
printf("numBytes copied is %i
", sizeof(buff));
Then once you have it as char * array you can use the freeimage loadFromMemory functions - which I think would be better than loadFromHandle. I think Freeimage can also determine the filetype from memory too with FreeImage_GetFileTypeFromMemory. There is more info in the freeimage docs: http://surfnet.dl.sourceforge.net/sourc-…-ge3100.pdf
The best thing to do would be to make a new class that extends the ofImage class - that way you don’t have to hack your ofImage code but you can still use the ofImage members and methods.
**note: this code was written against OF 0.04, likely you’ll need to change IMG->bmp to just bmp
**
haven’t thoroughly tested this, but I put it up here because it’s a start (also, it’s extending the base class, something we support as opposed to altering ofImage)
hope that helps!!
zach
#ifndef _OF_MEM_IMAGE_H_
#define _OF_MEM_IMAGE_H_
#include "ofImage.h"
class ofMemoryImage : public ofImage {
public :
void loadFromData(unsigned char * datasource, int len);
};
#endif
This is basically the code I posted above plus zach’s load from memory code.
To use just put the webImageLoader.h and .cpp in your src/ folder.
You can treat it just like an ofImage object but with the extra loadFromUrl function
webImageLoader.h
#pragma once
#include "ofMain.h"
#include "Poco/URIStreamOpener.h"
#include "Poco/StreamCopier.h"
#include "Poco/Path.h"
#include "Poco/URI.h"
#include "Poco/Exception.h"
#include "Poco/Net/HTTPStreamFactory.h"
#include <memory>
#include <iostream>
using Poco::URIStreamOpener;
using Poco::StreamCopier;
using Poco::Path;
using Poco::URI;
using Poco::Exception;
using Poco::Net::HTTPStreamFactory;
static bool factoryLoaded = false;
class webImageLoader : public ofImage {
public :
void loadFromUrl(string url);
};
webImageLoader.cpp
#include "webImageLoader.h"
void webImageLoader::loadFromUrl(string url){
//poco is not happy if we register the factory more than once
if(!factoryLoaded){
HTTPStreamFactory::registerFactory();
factoryLoaded = true;
}
//specify out url and open stream
URI uri(url);
std::auto_ptr<std::istream> pStr(URIStreamOpener::defaultOpener().open(uri));
//copy to our string
string str;
StreamCopier::copyToString(*pStr.get(), str);
//figure out how many bytes the image is and allocate
int bytesToRead = str.size();
char buff[bytesToRead];
memset(buff, 0, bytesToRead);
//copy the bytes from the string to our buffer
for(int i = 0; i < bytesToRead; i++){
buff[i] = str[i];
}
printf("numBytes copied is %i \n", sizeof(buff));
//if we already have a loaded image clear it
if(isValid()){
clear();
}
//create a freeimage memory handle from the buffer address
FIMEMORY *hmem = NULL;
hmem = FreeImage_OpenMemory((BYTE *)buff, bytesToRead);
if (hmem == NULL){ printf("couldn't create memory handle! \n"); return; }
//get the file type!
FREE_IMAGE_FORMAT fif = FreeImage_GetFileTypeFromMemory(hmem);
//make the image!!
bmp = FreeImage_LoadFromMemory(fif, hmem, 0);
//free our memory
FreeImage_CloseMemory(hmem);
if (bmp == NULL){ printf("couldn't create bmp! \n"); return; }
//flip it!
FreeImage_FlipVertical(bmp);
update();
}
thanks for the link. just out of curiosity, what does this line return for you?
//get the file type!
FREE_IMAGE_FORMAT fif = FreeImage_GetFileTypeFromMemory(hmem);
i’m getting a -1, which i guess means that it’s unable to determine the file type. and if i hardcode FIF_JPEG into FreeImage_LoadFromMemory, my app crashes.
Hey guys, I updated webImageLoader.cpp for OF 057 and possibly beyond (which nicely already has Poco inside of it). Let me know if you have any problems
#include "webImageLoader.h"
void webImageLoader::loadFromUrl(string url){
//poco is not happy if we register the factory more than once
if(!factoryLoaded){
HTTPStreamFactory::registerFactory();
factoryLoaded = true;
}
//specify out url and open stream
URI uri(url);
std::auto_ptr<std::istream> pStr(URIStreamOpener::defaultOpener().open(uri));
//copy to our string
string str;
StreamCopier::copyToString(*pStr.get(), str);
//figure out how many bytes the image is and allocate
int bytesToRead = str.size();
char buff[bytesToRead];
memset(buff, 0, bytesToRead);
//copy the bytes from the string to our buffer
for(int i = 0; i < bytesToRead; i++){
buff[i] = str[i];
}
printf("numBytes copied is %i \n", sizeof(buff));
//if we already have a loaded image clear it
// if(isValid()){
clear();
// }
//create a freeimage memory handle from the buffer address
FIMEMORY *hmem = NULL;
hmem = FreeImage_OpenMemory((BYTE *)buff, bytesToRead);
if (hmem == NULL){ printf("couldn't create memory handle! \n"); return; }
//get the file type!
FREE_IMAGE_FORMAT fif = FreeImage_GetFileTypeFromMemory(hmem);
//make the image!!
putBmpIntoPixels(FreeImage_LoadFromMemory(fif, hmem, 0), myPixels);
// bmp = FreeImage_LoadFromMemory(fif, hmem, 0);
//free our memory
FreeImage_CloseMemory(hmem);
if (getBmpFromPixels(myPixels) == NULL){ printf("couldn't create bmp! \n"); return; }
//flip it!
FreeImage_FlipVertical(getBmpFromPixels(myPixels));
if (myPixels.bAllocated == true && bUseTexture == true){
tex.allocate(myPixels.width, myPixels.height, myPixels.glDataType);
}
swapRgb(myPixels);
update();
}
I was trying to use the webImageLoader class and ran across this error? I’m new to oF but I suspect this is a remnant of a constant that used to exist that doesn’t anymore.
error: 'BYTE' was not declared in this scope
Any help is much appreciated, thanks!
edit: nevermind, just changed it to unsigned char * and we’ll see how that works, but now I’m getting a SIGABRT program error but that’s probably just me.
I was trying to use the webImageLoader class and ran across this error? I’m new to oF but I suspect this is a remnant of a constant that used to exist that doesn’t anymore.
error: 'BYTE' was not declared in this scope
Any help is much appreciated, thanks!
edit: nevermind, just changed it to unsigned char * and we’ll see how that works, but now I’m getting a SIGABRT program error but that’s probably just me.[/quote]
hey !
Did you solve this error?
Im on the same situation
I was trying to use the webImageLoader class and ran across this error? I’m new to oF but I suspect this is a remnant of a constant that used to exist that doesn’t anymore.
Code:
error: ‘BYTE’ was not declared in this scope
Any help is much appreciated, thanks!
edit: nevermind, just changed it to unsigned char * and we’ll see how that works, but now I’m getting a SIGABRT program error but that’s probably just me.
just same problem for me.
just changed to ‘Byte’ and it works, but now I’m getting a EXEC_BAD_ACCESS at
