Question on Custom Data Training about mnc HOT 3 CLOSED

1. Firstly, the mask_size has no relation with the number of classes. The mask size is the size of our mask regression output (A inner product layer with num_output = MASK_SIZE x MASK_SIZE) in stage 2/4.

2)&3) You also need to notice that the test_iter = 8 in my solver.prototxt. So every iteration consists 8 forward/backward operations. But it's still seems too slow for your experiments, what's your hardward configuration? And for the number of training iters, I believe you should try which is the best training iters by hand.

4. The accuracy will be highly affected by the number of background samples per batch, since background is much easier to be correctly classified. In your case, it seems there are too many background samples which results no instances are detected while the accuracy is very high.

5. Could you give more information about this issue? I didn't fully understand your description.

from mnc.

Hi @suhalim9, have you solved your problem, seems like we have similar problem. I also want to train MNC using my own dataset and the dataset only has one type of object. If you have solved your problem, could you share some experience please?

from mnc.

Hi @wuzheng-sjtu ,
To be honest, I ended up letting it trained slowly. My training images are pretty high resolutions so definitely took way longer than expected. I used the default iteration number but stopped at ~20000 iterations (after several days) because loss became -inf. I took the latest one that loss stayed normal (I don't remember the exact iteration number).

But I still have a problem with the accuracy. My object type is very simple without not many visible features (not like face, animal, etc.) So I wondered if my issue was because of the nature of the object.

In summary, I didn't see much success with the MNC model for the object I wanted to detect. But having more iterations helped a bit. I also used the 5 stage, which seemed slightly better than the 3 stage. I don't think my experience would help you..

If you have a success story, please share. :)

from mnc.