Retiring BLAM and announcing fSpy - a stand alone camera matching app

I’m unable to install the plugin. Could any one help? I’ve tried manually installing all the three .py files inside the blender addon folder, and on both v2.79 and v2.8. The blender plugin for some reason doesn’t install.

Download the latest release ( from here and tell Blender to install the downloaded zip-file (as opposed to the individual files).

1 Like

Just figured it like 5 mins back and even tested it out. Thanks a lot for the prompt response as well as the amazing tool! And if you don’t mind me suggesting​:sweat_smile: , bit more description it would be helpful to a lot of people :slight_smile:

You legend! My first time using this and it worked a treat. Awesome stuff mate. Thanks a million. This one will stay in the tool belt for a long time.


Can anyone explain this to me ?
If the number of vanishing points is just one, there are two red lines and one blue line.

This is confusing to me.
Shouldn’t there be just one line to establish horizon and that’s it ? Thanks.
Which one is the horizon ? The Blue line ? The two lines ? SO SORRY for the confusion.

If I got this right you only need 3 lines if you have one vanishing point, because the horizon line is orthogonal to the Z line. This means that once the vanishing point is established with two lines, the focal length is already determined. The third line is just for the tilt, not the focal length. And you don’t need 3 coordinates for one vanishing point, because the third line is just orthogonal to the plane determined by the other two coordinates.

Thank you, so say a picture is perfectly leveled, we will only need two lines for perspective and we will have to be REALLY CAREFUL lining up the third horizon line isn’t it ? Is there a button that makes the horizon line perfectly horizontally straight ? Moving the two points HOPING that it will be horizontally straight is just a bad idea.

Well fspy is just a tool to give you the values as precisely as it can. Once you are actually in blender and matching the camera, that is where you have to make a decision. If you know that the horizon line is perfectly balanced, then you can obviously ignore the tilt value that fspy calculated and use your better judgement, since the horizon line doesn’t affect the focal length anyway.

Thank you.

@stuffmatic I noticed a couple of minor issues which I wanted to share - maybe you’d like to have a look on them:

  • The title of the app window remains ‘Untitled’ after saving a file. Opening a saved file doesn’t update the ‘Untitled’ title either,
  • Hitting ctrl+S (or ctrl+shift+S) brings the path to fSpy location - I think I would be handy to land on the image location instead.

Since it might be OS specific, I’m on Linux. App version fspy-1.0.3-x86_64.AppImage

Would it be possible to Paste into fSpy from clipboard? I really like using copy paste as well as grabbing screenshots and pasting them quickly without getting bogged down with files and folders.

Also an advanced consideration: could it be possible to Copy and Paste a camera from fSpy into Blender?

any update for this about the bug in background image ( not transparent ) ?

Hi, any plans to add lens distortion settings (k1, k2, k3)?
Something like marking lines that should be straight with bezier curves and compute distortion from that.

Hi stuffmatic.
I noticed a bug in the importer today, and it is related to units.
For example, if in fSpy I mark a specific area in millimeters, after importing into blender, addon changes scene “Unit Scale” to “0.001”.
As a result, the distance between camera and object reaches several kilometers.
On the other hand, if I set units to meters in fSpy and importing file, “Unit Scale” it’s ok, but addon changes the default “Length” units to meters.