openface/batch-represent/dataset.lua

411 lines
14 KiB
Lua

-- Source: https://github.com/soumith/imagenet-multiGPU.torch/blob/master/dataset.lua
require 'torch'
torch.setdefaulttensortype('torch.FloatTensor')
local ffi = require 'ffi'
local dir = require 'pl.dir'
local argcheck = require 'argcheck'
require 'sys'
require 'xlua'
require 'image'
local dataset = torch.class('dataLoader')
local initcheck = argcheck{
pack=true,
help=[[
A dataset class for images in a flat folder structure (folder-name is class-name).
Optimized for extremely large datasets (upwards of 14 million images).
Tested only on Linux (as it uses command-line linux utilities to scale up)
]],
{check=function(paths)
local out = true;
for _,v in ipairs(paths) do
if type(v) ~= 'string' then
print('paths can only be of string input');
out = false
end
end
return out
end,
name="paths",
type="table",
help="Multiple paths of directories with images"},
{name="sampleSize",
type="table",
help="a consistent sample size to resize the images"},
{name="split",
type="number",
help="Percentage of split to go to Training"
},
{name="samplingMode",
type="string",
help="Sampling mode: random | balanced ",
default = "balanced"},
{name="verbose",
type="boolean",
help="Verbose mode during initialization",
default = false},
{name="loadSize",
type="table",
help="a size to load the images to, initially",
opt = true},
{name="forceClasses",
type="table",
help="If you want this loader to map certain classes to certain indices, "
.. "pass a classes table that has {classname : classindex} pairs."
.. " For example: {3 : 'dog', 5 : 'cat'}"
.. "This function is very useful when you want two loaders to have the same "
.. "class indices (trainLoader/testLoader for example)",
opt = true},
{name="sampleHookTrain",
type="function",
help="applied to sample during training(ex: for lighting jitter). "
.. "It takes the image path as input",
opt = true},
{name="sampleHookTest",
type="function",
help="applied to sample during testing",
opt = true},
}
function dataset:__init(...)
-- argcheck
local args = initcheck(...)
print(args)
for k,v in pairs(args) do self[k] = v end
if not self.loadSize then self.loadSize = self.sampleSize; end
if not self.sampleHookTrain then self.sampleHookTrain = self.defaultSampleHook end
if not self.sampleHookTest then self.sampleHookTest = self.defaultSampleHook end
-- find class names
self.classes = {}
local classPaths = {}
if self.forceClasses then
for k,v in pairs(self.forceClasses) do
self.classes[k] = v
classPaths[k] = {}
end
end
local function tableFind(t, o) for k,v in pairs(t) do if v == o then return k end end end
-- loop over each paths folder, get list of unique class names,
-- also store the directory paths per class
-- for each class,
for _,path in ipairs(self.paths) do
local dirs = dir.getdirectories(path);
for _,dirpath in ipairs(dirs) do
local class = paths.basename(dirpath)
local idx = tableFind(self.classes, class)
if not idx then
table.insert(self.classes, class)
idx = #self.classes
classPaths[idx] = {}
end
if not tableFind(classPaths[idx], dirpath) then
table.insert(classPaths[idx], dirpath);
end
end
end
self.classIndices = {}
for k,v in ipairs(self.classes) do
self.classIndices[v] = k
end
-- define command-line tools, try your best to maintain OSX compatibility
local wc = 'wc'
local cut = 'cut'
local find = 'find'
if jit.os == 'OSX' then
wc = 'gwc'
cut = 'gcut'
find = 'gfind'
end
----------------------------------------------------------------------
-- Options for the GNU find command
local extensionList = {'jpg', 'png','JPG','PNG','JPEG', 'ppm', 'PPM', 'bmp', 'BMP'}
local findOptions = ' -iname "*.' .. extensionList[1] .. '"'
for i=2,#extensionList do
findOptions = findOptions .. ' -o -iname "*.' .. extensionList[i] .. '"'
end
-- find the image path names
self.imagePath = torch.CharTensor() -- path to each image in dataset
self.imageClass = torch.LongTensor() -- class index of each image (class index in self.classes)
self.classList = {} -- index of imageList to each image of a particular class
self.classListSample = self.classList -- the main list used when sampling data
print('running "find" on each class directory, and concatenate all'
.. ' those filenames into a single file containing all image paths for a given class')
-- so, generates one file per class
local classFindFiles = {}
for i=1,#self.classes do
classFindFiles[i] = os.tmpname()
end
local combinedFindList = os.tmpname();
local tmpfile = os.tmpname()
local tmphandle = assert(io.open(tmpfile, 'w'))
-- iterate over classes
for i, _ in ipairs(self.classes) do
-- iterate over classPaths
for _,path in ipairs(classPaths[i]) do
local command = find .. ' "' .. path .. '" ' .. findOptions
.. ' >>"' .. classFindFiles[i] .. '" \n'
tmphandle:write(command)
end
end
io.close(tmphandle)
os.execute('bash ' .. tmpfile)
os.execute('rm -f ' .. tmpfile)
print('now combine all the files to a single large file')
tmpfile = os.tmpname()
tmphandle = assert(io.open(tmpfile, 'w'))
-- concat all finds to a single large file in the order of self.classes
for i=1,#self.classes do
local command = 'cat "' .. classFindFiles[i] .. '" >>' .. combinedFindList .. ' \n'
tmphandle:write(command)
end
io.close(tmphandle)
os.execute('bash ' .. tmpfile)
os.execute('rm -f ' .. tmpfile)
--==========================================================================
print('load the large concatenated list of sample paths to self.imagePath')
local maxPathLength = tonumber(sys.fexecute(wc .. " -L '"
.. combinedFindList .. "' |"
.. cut .. " -f1 -d' '")) + 1
local length = tonumber(sys.fexecute(wc .. " -l '"
.. combinedFindList .. "' |"
.. cut .. " -f1 -d' '"))
assert(length > 0, "Could not find any image file in the given input paths")
assert(maxPathLength > 0, "paths of files are length 0?")
self.imagePath:resize(length, maxPathLength):fill(0)
local s_data = self.imagePath:data()
local count = 0
for line in io.lines(combinedFindList) do
ffi.copy(s_data, line)
s_data = s_data + maxPathLength
if self.verbose and count % 10000 == 0 then
xlua.progress(count, length)
end;
count = count + 1
end
self.numSamples = self.imagePath:size(1)
if self.verbose then print(self.numSamples .. ' samples found.') end
--==========================================================================
print('Updating classList and imageClass appropriately')
self.imageClass:resize(self.numSamples)
local runningIndex = 0
for i=1,#self.classes do
if self.verbose then xlua.progress(i, #(self.classes)) end
local clsLength = tonumber(sys.fexecute(wc .. " -l '"
.. classFindFiles[i] .. "' |"
.. cut .. " -f1 -d' '"))
if clsLength == 0 then
error('Class has zero samples: ' .. self.classes[i])
else
-- self.classList[i] = torch.linspace(runningIndex + 1, runningIndex + clsLength, clsLength):long()
self.classList[i] = torch.range(runningIndex + 1, runningIndex + clsLength):long()
self.imageClass[{{runningIndex + 1, runningIndex + clsLength}}]:fill(i)
end
runningIndex = runningIndex + clsLength
end
--==========================================================================
-- clean up temporary files
print('Cleaning up temporary files')
local tmpfilelistall = ''
for i=1,#(classFindFiles) do
tmpfilelistall = tmpfilelistall .. ' "' .. classFindFiles[i] .. '"'
if i % 1000 == 0 then
os.execute('rm -f ' .. tmpfilelistall)
tmpfilelistall = ''
end
end
os.execute('rm -f ' .. tmpfilelistall)
os.execute('rm -f "' .. combinedFindList .. '"')
--==========================================================================
if self.split == 100 then
self.testIndicesSize = 0
else
print('Splitting training and test sets to a ratio of '
.. self.split .. '/' .. (100-self.split))
self.classListTrain = {}
self.classListTest = {}
self.classListSample = self.classListTrain
local totalTestSamples = 0
-- split the classList into classListTrain and classListTest
for i=1,#self.classes do
local list = self.classList[i]
count = self.classList[i]:size(1)
local splitidx = math.floor((count * self.split / 100) + 0.5) -- +round
local perm = torch.randperm(count)
self.classListTrain[i] = torch.LongTensor(splitidx)
for j=1,splitidx do
self.classListTrain[i][j] = list[perm[j]]
end
if splitidx == count then -- all samples were allocated to train set
self.classListTest[i] = torch.LongTensor()
else
self.classListTest[i] = torch.LongTensor(count-splitidx)
totalTestSamples = totalTestSamples + self.classListTest[i]:size(1)
local idx = 1
for j=splitidx+1,count do
self.classListTest[i][idx] = list[perm[j]]
idx = idx + 1
end
end
end
-- Now combine classListTest into a single tensor
self.testIndices = torch.LongTensor(totalTestSamples)
self.testIndicesSize = totalTestSamples
local tdata = self.testIndices:data()
local tidx = 0
for i=1,#self.classes do
local list = self.classListTest[i]
if list:dim() ~= 0 then
local ldata = list:data()
for j=0,list:size(1)-1 do
tdata[tidx] = ldata[j]
tidx = tidx + 1
end
end
end
end
end
-- size(), size(class)
function dataset:size(class, list)
list = list or self.classList
if not class then
return self.numSamples
elseif type(class) == 'string' then
return list[self.classIndices[class]]:size(1)
elseif type(class) == 'number' then
return list[class]:size(1)
end
end
-- size(), size(class)
function dataset:sizeTrain(class)
if self.split == 0 then
return 0;
end
if class then
return self:size(class, self.classListTrain)
else
return self.numSamples - self.testIndicesSize
end
end
-- size(), size(class)
function dataset:sizeTest(class)
if self.split == 100 then
return 0
end
if class then
return self:size(class, self.classListTest)
else
return self.testIndicesSize
end
end
-- by default, just load the image and return it
function dataset:defaultSampleHook(imgpath)
local out = image.load(imgpath, 3, byte)
out = image.scale(out, self.sampleSize[3], self.sampleSize[2])
return out
end
-- getByClass
function dataset:getByClass(class)
local index = math.ceil(torch.uniform() * self.classListSample[class]:nElement())
local imgpath = ffi.string(torch.data(self.imagePath[self.classListSample[class][index]]))
return self:sampleHookTrain(imgpath)
end
-- converts a table of samples (and corresponding labels) to a clean tensor
local function tableToOutput(self, dataTable, scalarTable)
local data, scalarLabels, labels
local quantity = #scalarTable
local samplesPerDraw
if dataTable[1]:dim() == 3 then samplesPerDraw = 1
else samplesPerDraw = dataTable[1]:size(1) end
data = torch.Tensor(quantity * samplesPerDraw,
self.sampleSize[1], self.sampleSize[2], self.sampleSize[3])
scalarLabels = torch.LongTensor(quantity * samplesPerDraw)
labels = torch.LongTensor(quantity * samplesPerDraw, #(self.classes)):fill(-1)
for i=1,#dataTable do
local idx = (i-1)*samplesPerDraw
data[{{idx+1,idx+samplesPerDraw}}]:copy(dataTable[i])
scalarLabels[{{idx+1,idx+samplesPerDraw}}]:fill(scalarTable[i])
labels[{{idx+1,idx+samplesPerDraw},{scalarTable[i]}}]:fill(1)
end
return data, scalarLabels, labels
end
function dataset:get(i1, i2)
local indices, quantity
if type(i1) == 'number' then
if type(i2) == 'number' then -- range of indices
indices = torch.range(i1, i2);
quantity = i2 - i1 + 1;
else -- single index
indices = {i1}; quantity = 1
end
elseif type(i1) == 'table' then
indices = i1; quantity = #i1; -- table
elseif (type(i1) == 'userdata' and i1:nDimension() == 1) then
indices = i1; quantity = (#i1)[1]; -- tensor
else
error('Unsupported input types: ' .. type(i1) .. ' ' .. type(i2))
end
assert(quantity > 0)
-- now that indices has been initialized, get the samples
local dataTable = {}
local scalarTable = {}
for i=1,quantity do
-- load the sample
local idx = self.testIndices[indices[i]]
local imgpath = ffi.string(torch.data(self.imagePath[idx]))
local out = self:sampleHookTest(imgpath)
table.insert(dataTable, out)
table.insert(scalarTable, self.imageClass[idx])
end
local data, scalarLabels, labels = tableToOutput(self, dataTable, scalarTable)
return data, scalarLabels, labels
end
function dataset:test(quantity)
if self.split == 100 then
error('No test mode when you are not splitting the data')
end
local i = 1
local n = self.testIndicesSize
local qty = quantity or 1
return function ()
if i+qty-1 <= n then
local data, scalarLabelss, labels = self:get(i, i+qty-1)
i = i + qty
return data, scalarLabelss, labels
end
end
end
return dataset