Sometimes when buying a service, you can determine the honesty of a seller simply by looking at the images they provide.
It is quite difficult to determine the installation 100%. One can only assume and decide in which direction the scale will swing. They burn only because of the unprofessionalism of the renderer, because the data was broken, or because of fraud, well, and a few other factors
Now directly to the analysis.
1. Visual inspection.
This is the most important point, the human factor always plays a role. You need to carefully look at the B-splain (as I call these lines) or at the background of the document itself. For example, here we see gaps. This happens when the photo is not of a very high quality, it is worth asking for a photo change! Keep in mind that the maximum approximation can only be confusing. Zoom in step by step and compare with the rest of the picture. Of course, we include the head and logic.
It is important to take a good look at the photo. Such things are not allowed!
Any ghosting around the inserted object is pale! Always remember that the glow can depend on what color is reflected from the object, for example, we have a piece, the room has purple walls and the sun shines on the walls through the window, and the piece is next to the wall. Such factors can give a violet glow. So the glow does not always indicate that the installation has been made. Do not forget about shadows, if the light falls on one side, then the glow on one side and dimness on the other, when viewed in ELA - are quite natural, as in the example below (the name is blurred for obvious reasons, we do not pay attention to this):
It may seem that installation, but in fact it is the effect of the fact that sunlight falls on the pieces.
Here is a photo in its normal form (the name is blurred for obvious reasons)
We compare the fonts with the original, do not forget - there may be several original ones. We are looking for all the scans and compare each letter with the document sent to you. With regard to fonts, we also pay attention to the color of the font, if the renderer is lazy, it will not fit all the text into one font, changing only, for example, the full name. When zooming in, pixel structure, graininess and color transition sequence should be the same throughout the composition if the subject is made of the same matter. Pay attention to the tonality of the same colors. Think logically, for example, a felt-tip pen, pen and other similar objects in the middle of the strip will always be slightly darker (brushes, rollers, paint cans, and the like do not count) if there are places where the drawing object has been walked more than once, for example, the joints of the letter lines should always be darker.
Example # 1 - tonality of color in comparison with the rest of the text
Here you don't even need to look at the original - look how the letter s differs - it is darker. In addition, look at how many pixels of different tonality and what color transition on adjacent letters - the difference is obvious.
Here is a photo of the original:
Example # 2 - the absence of pixels of different tonality
Here we see an inscription on a piece of paper, i.e. in fact, materially, it is a sheet of paper, for a figure it is a single matter, which means that it should be the same when broken into pixels. We observe that the light part of the paper is divided into pixels of the same size and there is a tonality transition, the dark part is practically without a tonality transition and the pixels are not visible - obvious photoshop.
Photo of the original, as it should be:
Example # 3 - lack of logic
The inscription was allegedly made with a felt-tip pen, in some places in the middle of the letter line there are obvious light spots, although in the case of a felt-tip pen, the closer to the center, the richer the color, moreover, in the marked plane, the felt-tip pen had to pass through the same area twice, which means the shade should be darker and richer, but this is not.
Example No. 4 - incomprehensible borders, broken drawing
On this screen, you can see the borders of the rectangle, which were formed during the copying of the element. There shouldn't be such boundaries.
2. ELA analysis, extra pixels, EXIF, etc.
There are quite a few services for analyzing JPG, by the way, please note that many accept PNG and PDF, in which there is no exif and it is much more difficult to burn them, if they accept PDF PNG, then be sure to send the docks in this format! go to analysis!
LINK fotoforensics.com
The following tools are available:
Dijest - in fact, the properties of the file are not that important.
ELA - I will not quote clever words from Wikipedia, I will say what I think about this. This is a test that allows you to identify a discrepancy in the color gamut, look at the screen, the pixel in the photo was very large, so ate painted it in a dark color, if it were the other way around, the inserted element would have a higher expansion, it would be painted with multi-colored dots.
Hidden Pixels - A good tool that allows you to reveal hidden pixels when the checker writes! No hidden pixels "pay attention to the b / w squares superimposed on the photo, if you are a periscope))) and you will see a square that does not fit into the overall picture, editing is not unambiguous, but most likely!
JPEG% - Compression ratio, photo quality. Based on the indicators of this parameter, you can conduct an experiment by analyzing EXIF (metadata). If you see, for example, an iPhone in EXIF, fill in a photo from an iPhone on forensis and see the compression, if it is very different, you need to think and take action) in the same way, compare the weight of the photo allegedly provided to you from an iPhone, and take a picture yourself on the same iPhone model document, if the difference in weight is large, see above what to do.
Next comes Metadata, this is EXIF, seeing any mention of graphic editors there, permanent lock!
It is quite difficult to determine the installation 100%. One can only assume and decide in which direction the scale will swing. They burn only because of the unprofessionalism of the renderer, because the data was broken, or because of fraud, well, and a few other factors
Now directly to the analysis.
1. Visual inspection.
This is the most important point, the human factor always plays a role. You need to carefully look at the B-splain (as I call these lines) or at the background of the document itself. For example, here we see gaps. This happens when the photo is not of a very high quality, it is worth asking for a photo change! Keep in mind that the maximum approximation can only be confusing. Zoom in step by step and compare with the rest of the picture. Of course, we include the head and logic.
It is important to take a good look at the photo. Such things are not allowed!
Any ghosting around the inserted object is pale! Always remember that the glow can depend on what color is reflected from the object, for example, we have a piece, the room has purple walls and the sun shines on the walls through the window, and the piece is next to the wall. Such factors can give a violet glow. So the glow does not always indicate that the installation has been made. Do not forget about shadows, if the light falls on one side, then the glow on one side and dimness on the other, when viewed in ELA - are quite natural, as in the example below (the name is blurred for obvious reasons, we do not pay attention to this):
It may seem that installation, but in fact it is the effect of the fact that sunlight falls on the pieces.
Here is a photo in its normal form (the name is blurred for obvious reasons)
We compare the fonts with the original, do not forget - there may be several original ones. We are looking for all the scans and compare each letter with the document sent to you. With regard to fonts, we also pay attention to the color of the font, if the renderer is lazy, it will not fit all the text into one font, changing only, for example, the full name. When zooming in, pixel structure, graininess and color transition sequence should be the same throughout the composition if the subject is made of the same matter. Pay attention to the tonality of the same colors. Think logically, for example, a felt-tip pen, pen and other similar objects in the middle of the strip will always be slightly darker (brushes, rollers, paint cans, and the like do not count) if there are places where the drawing object has been walked more than once, for example, the joints of the letter lines should always be darker.
Example # 1 - tonality of color in comparison with the rest of the text
Here you don't even need to look at the original - look how the letter s differs - it is darker. In addition, look at how many pixels of different tonality and what color transition on adjacent letters - the difference is obvious.
Here is a photo of the original:
Example # 2 - the absence of pixels of different tonality
Here we see an inscription on a piece of paper, i.e. in fact, materially, it is a sheet of paper, for a figure it is a single matter, which means that it should be the same when broken into pixels. We observe that the light part of the paper is divided into pixels of the same size and there is a tonality transition, the dark part is practically without a tonality transition and the pixels are not visible - obvious photoshop.
Photo of the original, as it should be:
Example # 3 - lack of logic
The inscription was allegedly made with a felt-tip pen, in some places in the middle of the letter line there are obvious light spots, although in the case of a felt-tip pen, the closer to the center, the richer the color, moreover, in the marked plane, the felt-tip pen had to pass through the same area twice, which means the shade should be darker and richer, but this is not.
Example No. 4 - incomprehensible borders, broken drawing
On this screen, you can see the borders of the rectangle, which were formed during the copying of the element. There shouldn't be such boundaries.
2. ELA analysis, extra pixels, EXIF, etc.
There are quite a few services for analyzing JPG, by the way, please note that many accept PNG and PDF, in which there is no exif and it is much more difficult to burn them, if they accept PDF PNG, then be sure to send the docks in this format! go to analysis!
LINK fotoforensics.com
The following tools are available:
Dijest - in fact, the properties of the file are not that important.
ELA - I will not quote clever words from Wikipedia, I will say what I think about this. This is a test that allows you to identify a discrepancy in the color gamut, look at the screen, the pixel in the photo was very large, so ate painted it in a dark color, if it were the other way around, the inserted element would have a higher expansion, it would be painted with multi-colored dots.
Hidden Pixels - A good tool that allows you to reveal hidden pixels when the checker writes! No hidden pixels "pay attention to the b / w squares superimposed on the photo, if you are a periscope))) and you will see a square that does not fit into the overall picture, editing is not unambiguous, but most likely!
JPEG% - Compression ratio, photo quality. Based on the indicators of this parameter, you can conduct an experiment by analyzing EXIF (metadata). If you see, for example, an iPhone in EXIF, fill in a photo from an iPhone on forensis and see the compression, if it is very different, you need to think and take action) in the same way, compare the weight of the photo allegedly provided to you from an iPhone, and take a picture yourself on the same iPhone model document, if the difference in weight is large, see above what to do.
Next comes Metadata, this is EXIF, seeing any mention of graphic editors there, permanent lock!
