Where to get negative sample images for Haar training? [closed]

Question

I need a collection of sample images to train a Haar-based classifier for face detection. I read that a ratio of 2 negative examples for each positive example is acceptable. I searched around the web and found many databases containing positive examples to train my classifier (that is, images that contain faces), however, I can't any database with negative examples. Right now, I have over 18000 positive examples. Where can I find 2000 or more negative examples?

Tinsmith

Could you please try and fix the spelling/grammar issues. As of now, your post is unreadable. – Anacoluthon

which word you doesn't understand it ? – Tinsmith

The entire piece, you fixed some spelling errors, but it still is really confusing. Are you asking for how to extract the background? How to find a database of images? How the haar training works to read an image, and how you can generate sample images? Any of these are possible interpretations of your question. – Anacoluthon

no I ask where can i find negative image more than 20000 downloading it from google take long time – Tinsmith

just use any images where the object-to-detect isnt present. You can use rotations/scales and subimages of those negative samples too. – Eponymous

i know any image but i need more than 20000 any way for download 20000 image from google street ? – Tinsmith

I guess you could take a lot of screenshots... Honestly, without more information I don't know what else to tell you. What you are asking for really is vague. (Maybe checkout MIT, Carnegie, etc. They often have databases of images. [Although not likely 20k, that is a REALLY big amount]. ) You might have to generate them yourself if you need that many. – Anacoluthon

The link you provided has roughly 5k negative images, what are you trying to train it to do that you need much more than that? – Anacoluthon

i have 15000 positive image so i must have more than 15000 for negative for this tow days i have now 8000 – Tinsmith

You still haven't said what "object" you are training it to find. How are we supposed to suggest the correct database without this information. – Anacoluthon

i say its face frontal and profile – Tinsmith

now i just test on 1200 positive image when its on stage 7 its detect some faces with some false detect but when its be in stage 13 its dosn't detect any thing why ? – Tinsmith

Answer 1

use http://tutorial-haartraining.googlecode.com/svn/trunk/data/negatives/

or any other image set that has no objects you need to recognize

NOTE: the number of samples you mention is too big, you don't need so much to obtain high accuracy

Kaki

i want to use 30000 image for face detection did thats too big how much must i use ? for best detection left side and frontal face – Tinsmith

the original cascade in openCV uses 5000 positive samples - but for front faces only. in your case it might be increased or split in two cascades. which is a better approach - better to check on real data. – Kaki