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| 2013-07-30 05:26:21 -0600 | marked best answer | about traincascade paremeters, samples, and other... Hi all. Firs of all I want to tell, my question contain many sub questions, answers to which already exist, but they are not complete or ambiguous. So first - maxFalseAlarmRate - I have most problems with it. If this is max - it mean current false alarm less than required. But in source we can see if(tempLeafFARate <= requiredLeafFARate) then "Required leaf false alarm rate achieved." It's funny - I can make maxFalseAlarmRate = 0 and newer have this error? It's opencv 2.4.2 fault? And so - what mean maxFalseAlarmRate at all. How can I calculate it? Why we have false alarm if in negatives there are no object? Next - if there are false alarm, my positives are bad? Size - if e.g. I have picture 100x200 what size in vec-file will be most appropriate? 10x20? How to calculate minHitRate? There says - samples must be unique. If samples are from one picture it bad? Why? They also will be unique in one object. If I created many samples from many objects, how can I pack them in vec-file? About vec-file. How many samples should it contain? How many positives and negatives are optimal and how to choose the optimal number of stages? There are interesting error "Bad argument (Can not get new positive sample. The most possible reason is insufficient count of samples in given vec-file.)". I found formula vec-file has to contain >= (numPose + (numStages-1) * (1 - minHitRate) * numPose) + S, where S is a count of samples from vec-file. If parametr numPos - number of samples in every stage, why I cant get num of samples in vec-file and divide it on num of stages? But in formula vec-file has to contain >= x + count of samples from vec-file. Maybe I understan something, "vec-file has to contain" and "count of samples from vec-file" this is not the same thing? numPose - is number of positive samples used in training for every classifier stage? What exactly does parameter -numPos means? And how to choose it? When I start training I see number of stages, next e.g. Pos count : consumed 200 : 232 why consumed is more than count? After that row there is no output info long time, after - Neg count : acceptance ratio What is acceptance ratio? Next - precalculaton time - I cant understand what is it? And the end is table with number, hit rate and false alarm rate. What mean this rows and hr and fa? hr and fa for what? Also i want to know more about paremeters bt , weightTrimRate, maxDepth, maxWeakCount і mode. What tipe (bt) use? How calculate weightTrimRate, maxDepth, maxWeakCount, and what mode is better? P.S. Why it takes so long before outputing numNeg Is it normal that createsample is working 4 days and it is just 6th step? How could it be : I've put falseAlarmRate=0 but there is condition in source code: 1>=falseAlarmRate >0 and it still starts without errors and warnings. About performance. I built opencv with tbb. Traincascade use 26% cpu, but I don ... |
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