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deepmatting_seg.lua
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deepmatting_seg.lua
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require 'torch'
require 'nn'
require 'image'
require 'optim'
require 'loadcaffe'
require 'libcuda_utils'
require 'cutorch'
require 'cunn'
local matio = require 'matio'
local cmd = torch.CmdLine()
-- Basic options
cmd:option('-style_image', 'examples/inputs/seated-nude.jpg', 'Style target image')
cmd:option('-content_image', 'examples/inputs/tubingen.jpg','Content target image')
cmd:option('-style_seg', '', 'Style segmentation')
cmd:option('-style_seg_idxs', '', 'Style seg idxs')
cmd:option('-content_seg', '', 'Content segmentation')
cmd:option('-content_seg_idxs', '', 'Content seg idxs')
cmd:option('-init_image', 'examples/inputs/init.jpg', 'Initial image')
cmd:option('-gpu', 0, 'Zero-indexed ID of the GPU to use; for CPU mode set -gpu = -1')
-- Optimization options
cmd:option('-content_weight', 5e0)
cmd:option('-style_weight', 1e2)
cmd:option('-tv_weight', 1e-3)
cmd:option('-num_iterations', 1000)
-- Local affine params
cmd:option('-lambda', 1e4)
cmd:option('-patch', 3)
cmd:option('-eps', 1e-7)
-- Reconstruct best local affine using joint bilateral smoothing
cmd:option('-f_radius', 7)
cmd:option('-f_edge', 0.05)
-- Output options
cmd:option('-print_iter', 1)
cmd:option('-save_iter', 100)
cmd:option('-output_image', 'out.png')
cmd:option('-index', 1)
cmd:option('-serial', 'serial_example')
-- Other options
cmd:option('-proto_file', 'models/VGG_ILSVRC_19_layers_deploy.prototxt')
cmd:option('-model_file', 'models/VGG_ILSVRC_19_layers.caffemodel')
cmd:option('-backend', 'nn', 'nn|cudnn|clnn')
cmd:option('-cudnn_autotune', false)
cmd:option('-seed', 612)
cmd:option('-content_layers', 'relu4_2', 'layers for content')
cmd:option('-style_layers', 'relu1_1,relu2_1,relu3_1,relu4_1,relu5_1', 'layers for style')
local function main(params)
cutorch.setDevice(params.gpu + 1)
cutorch.setHeapTracking(true)
torch.manualSeed(params.seed)
idx = cutorch.getDevice()
print('gpu, idx = ', params.gpu, idx)
-- content: pitie transferred input image
local content_image = image.load(params.content_image, 3)
local content_image_caffe = preprocess(content_image):float():cuda()
local content_layers = params.content_layers:split(",")
-- style: target model image
local style_image = image.load(params.style_image, 3)
local style_image_caffe = preprocess(style_image):float():cuda()
local style_layers = params.style_layers:split(",")
local c, h, w = content_image:size(1), content_image:size(2), content_image:size(3)
local _, h2, w2 = style_image:size(1), style_image:size(2), style_image:size(3)
local index = params.index
-- init: used for initialize the image
local init_image = image.load(params.init_image, 3)
init_image = image.scale(init_image, w, h, 'bilinear')
local init_image_caffe = preprocess(init_image):float():cuda()
-- segmentation images
--[
local content_seg = image.load(params.content_seg, 3)
content_seg = image.scale(content_seg, w, h, 'bilinear')
local style_seg = image.load(params.style_seg, 3)
style_seg = image.scale(style_seg, w2, h2, 'bilinear')
local color_codes = {'blue', 'green', 'black', 'white', 'red', 'yellow', 'grey', 'lightblue', 'purple'}
local color_content_masks, color_style_masks = {}, {}
for j = 1, #color_codes do
local content_mask_j = ExtractMask(content_seg, color_codes[j])
local style_mask_j = ExtractMask(style_seg, color_codes[j])
table.insert(color_content_masks, content_mask_j)
table.insert(color_style_masks, style_mask_j)
end
--]]
-- Set up the network, inserting style and content loss modules
local content_losses, style_losses = {}, {}
local next_content_idx, next_style_idx = 1, 1
local net = nn.Sequential()
if params.tv_weight > 0 then
local tv_mod = nn.TVLoss(params.tv_weight):float():cuda()
net:add(tv_mod)
end
-- load VGG-19 network
local cnn = loadcaffe.load(params.proto_file, params.model_file, params.backend):float():cuda()
-- load matting laplacian
local CSR_fn = 'gen_laplacian/Input_Laplacian_'..tostring(params.patch)..'x'..tostring(params.patch)..'_1e-7_CSR' .. tostring(index) .. '.mat'
print('loading matting laplacian...', CSR_fn)
local CSR = matio.load(CSR_fn).CSR:cuda()
paths.mkdir(tostring(params.serial))
print('Exp serial:', params.serial)
for i = 1, #cnn do
if next_content_idx <= #content_layers or next_style_idx <= #style_layers then
local layer = cnn:get(i)
local name = layer.name
local layer_type = torch.type(layer)
local is_pooling = (layer_type == 'nn.SpatialMaxPooling' or layer_type == 'cudnn.SpatialMaxPooling')
local is_conv = (layer_type == 'nn.SpatialConvolution' or layer_type == 'cudnn.SpatialConvolution')
net:add(layer)
if is_pooling then
for k = 1, #color_codes do
color_content_masks[k] = image.scale(color_content_masks[k], math.ceil(color_content_masks[k]:size(2)/2), math.ceil(color_content_masks[k]:size(1)/2))
color_style_masks[k] = image.scale(color_style_masks[k], math.ceil(color_style_masks[k]:size(2)/2), math.ceil(color_style_masks[k]:size(1)/2))
end
elseif is_conv then
local sap = nn.SpatialAveragePooling(3,3,1,1,1,1):float()
for k = 1, #color_codes do
color_content_masks[k] = sap:forward(color_content_masks[k]:repeatTensor(1,1,1))[1]:clone()
color_style_masks[k] = sap:forward(color_style_masks[k]:repeatTensor(1,1,1))[1]:clone()
end
end
color_content_masks = deepcopy(color_content_masks)
color_style_masks = deepcopy(color_style_masks)
if name == content_layers[next_content_idx] then
print("Setting up content layer", i, ":", layer.name)
local target = net:forward(content_image_caffe):clone()
local loss_module = nn.ContentLoss(params.content_weight, target, false):float():cuda()
net:add(loss_module)
table.insert(content_losses, loss_module)
next_content_idx = next_content_idx + 1
end
if name == style_layers[next_style_idx] then
print("Setting up style layer ", i, ":", layer.name)
local gram = GramMatrix():float():cuda()
local target_features = net:forward(style_image_caffe):clone()
local target_grams = {}
for j = 1, #color_codes do
local l_style_mask_ori = color_style_masks[j]:clone():cuda()
local l_style_mask = l_style_mask_ori:repeatTensor(1,1,1):expandAs(target_features)
local l_style_mean = l_style_mask_ori:mean()
local masked_target_features = torch.cmul(l_style_mask, target_features)
local masked_target_gram = gram:forward(masked_target_features):clone()
if l_style_mean > 0 then
masked_target_gram:div(target_features:nElement() * l_style_mean)
end
table.insert(target_grams, masked_target_gram)
end
local loss_module = nn.StyleLossWithSeg(params.style_weight, target_grams, color_content_masks, color_codes, next_style_idx, false):float():cuda()
net:add(loss_module)
table.insert(style_losses, loss_module)
next_style_idx = next_style_idx + 1
end
end
end
-- We don't need the base CNN anymore, so clean it up to save memory.
cnn = nil
for i=1,#net.modules do
local module = net.modules[i]
if torch.type(module) == 'nn.SpatialConvolutionMM' then
-- remove these, not used, but uses gpu memory
module.gradWeight = nil
module.gradBias = nil
end
end
collectgarbage()
local mean_pixel = torch.CudaTensor({103.939, 116.779, 123.68})
local meanImage = mean_pixel:view(3, 1, 1):expandAs(content_image_caffe)
local img = init_image_caffe
-- Run it through the network once to get the proper size for the gradient
-- All the gradients will come from the extra loss modules, so we just pass
-- zeros into the top of the net on the backward pass.
local y = net:forward(img)
local dy = img.new(#y):zero()
-- Declaring this here lets us access it in maybe_print
local optim_state = {
maxIter = params.num_iterations,
tolX = 0, tolFun = -1,
verbose=true,
}
local function maybe_print(t, loss)
local verbose = (params.print_iter > 0 and t % params.print_iter == 0)
if verbose then
print(string.format('Iteration %d / %d', t, params.num_iterations))
for i, loss_module in ipairs(content_losses) do
print(string.format(' Content %d loss: %f', i, loss_module.loss))
end
for i, loss_module in ipairs(style_losses) do
print(string.format(' Style %d loss: %f', i, loss_module.loss))
end
print(string.format(' Total loss: %f', loss))
end
end
local function maybe_save(t)
local should_save = params.save_iter > 0 and t % params.save_iter == 0
should_save = should_save or t == params.num_iterations
if should_save then
local disp = deprocess(img:double())
disp = image.minmax{tensor=disp, min=0, max=1}
local filename = params.serial .. '/out' .. tostring(index) .. '_t_' .. tostring(t) .. '.png'
image.save(filename, disp)
end
end
local num_calls = 0
local function feval(AffineModel)
num_calls = num_calls + 1
local output = torch.add(img, meanImage)
local input = torch.add(content_image_caffe, meanImage)
net:forward(img)
local gradient_VggNetwork = net:updateGradInput(img, dy)
local gradient_LocalAffine = MattingLaplacian(output, CSR, h, w):mul(params.lambda)
if num_calls % params.save_iter == 0 then
local best = SmoothLocalAffine(output, input, params.eps, params.patch, h, w, params.f_radius, params.f_edge)
fn = params.serial .. '/best' .. tostring(params.index) .. '_t_' .. tostring(num_calls) .. '.png'
image.save(fn, best)
end
local grad = torch.add(gradient_VggNetwork, gradient_LocalAffine)
local loss = 0
for _, mod in ipairs(content_losses) do
loss = loss + mod.loss
end
for _, mod in ipairs(style_losses) do
loss = loss + mod.loss
end
maybe_print(num_calls, loss)
-- maybe_save(num_calls)
collectgarbage()
-- optim.lbfgs expects a vector for gradients
return loss, grad:view(grad:nElement())
end
-- Run optimization.
local x, losses = optim.lbfgs(feval, img, optim_state)
end
function MattingLaplacian(output, CSR, h, w)
local N, c = CSR:size(1), CSR:size(2)
local CSR_rowIdx = torch.CudaIntTensor(N):copy(torch.round(CSR[{{1,-1},1}]))
local CSR_colIdx = torch.CudaIntTensor(N):copy(torch.round(CSR[{{1,-1},2}]))
local CSR_val = torch.CudaTensor(N):copy(CSR[{{1,-1},3}])
local output01 = torch.div(output, 256.0)
local grad = cuda_utils.matting_laplacian(output01, h, w, CSR_rowIdx, CSR_colIdx, CSR_val, N)
grad:div(256.0)
return grad
end
function SmoothLocalAffine(output, input, epsilon, patch, h, w, f_r, f_e)
local output01 = torch.div(output, 256.0)
local input01 = torch.div(input, 256.0)
local filter_radius = f_r
local sigma1, sigma2 = filter_radius / 3, f_e
local best01= cuda_utils.smooth_local_affine(output01, input01, epsilon, patch, h, w, filter_radius, sigma1, sigma2)
return best01
end
function ErrorMapLocalAffine(output, input, epsilon, patch, h, w)
local output01 = torch.div(output, 256.0)
local input01 = torch.div(input, 256.0)
local err_map, best01, Mt_M, invMt_M = cuda_utils.error_map_local_affine(output01, input01, epsilon, patch, h, w)
return err_map, best01
end
function build_filename(output_image, iteration)
local ext = paths.extname(output_image)
local basename = paths.basename(output_image, ext)
local directory = paths.dirname(output_image)
return string.format('%s/%s_%d.%s',directory, basename, iteration, ext)
end
-- Preprocess an image before passing it to a Caffe model.
-- We need to rescale from [0, 1] to [0, 255], convert from RGB to BGR,
-- and subtract the mean pixel.
function preprocess(img)
local mean_pixel = torch.DoubleTensor({103.939, 116.779, 123.68})
local perm = torch.LongTensor{3, 2, 1}
img = img:index(1, perm):mul(256.0)
mean_pixel = mean_pixel:view(3, 1, 1):expandAs(img)
img:add(-1, mean_pixel)
return img
end
-- Undo the above preprocessing.
function deprocess(img)
local mean_pixel = torch.DoubleTensor({103.939, 116.779, 123.68})
mean_pixel = mean_pixel:view(3, 1, 1):expandAs(img)
img = img + mean_pixel
local perm = torch.LongTensor{3, 2, 1}
img = img:index(1, perm):div(256.0)
return img
end
function deepcopy(orig)
local orig_type = type(orig)
local copy
if orig_type == 'table' then
copy = {}
for orig_key, orig_value in next, orig, nil do
copy[deepcopy(orig_key)] = deepcopy(orig_value)
end
setmetatable(copy, deepcopy(getmetatable(orig)))
else -- number, string, boolean, etc
copy = orig
end
return copy
end
-- Define an nn Module to compute content loss in-place
local ContentLoss, parent = torch.class('nn.ContentLoss', 'nn.Module')
function ContentLoss:__init(strength, target, normalize)
parent.__init(self)
self.strength = strength
self.target = target
self.normalize = normalize or false
self.loss = 0
self.crit = nn.MSECriterion()
end
function ContentLoss:updateOutput(input)
if input:nElement() == self.target:nElement() then
self.loss = self.crit:forward(input, self.target) * self.strength
else
print('WARNING: Skipping content loss')
end
self.output = input
return self.output
end
function ContentLoss:updateGradInput(input, gradOutput)
if input:nElement() == self.target:nElement() then
self.gradInput = self.crit:backward(input, self.target)
end
if self.normalize then
self.gradInput:div(torch.norm(self.gradInput, 1) + 1e-8)
end
self.gradInput:mul(self.strength)
self.gradInput:add(gradOutput)
return self.gradInput
end
-- Returns a network that computes the CxC Gram matrix from inputs
-- of size C x H x W
function GramMatrix()
local net = nn.Sequential()
net:add(nn.View(-1):setNumInputDims(2))
local concat = nn.ConcatTable()
concat:add(nn.Identity())
concat:add(nn.Identity())
net:add(concat)
net:add(nn.MM(false, true))
return net
end
-- Define an nn Module to compute style loss in-place
local StyleLoss, parent = torch.class('nn.StyleLoss', 'nn.Module')
function StyleLoss:__init(strength, target, normalize)
parent.__init(self)
self.normalize = normalize or false
self.strength = strength
self.target = target
self.loss = 0
self.gram = GramMatrix()
self.G = nil
self.crit = nn.MSECriterion()
end
function StyleLoss:updateOutput(input)
self.G = self.gram:forward(input)
self.G:div(input:nElement())
self.loss = self.crit:forward(self.G, self.target)
self.loss = self.loss * self.strength
self.output = input
return self.output
end
function StyleLoss:updateGradInput(input, gradOutput)
local dG = self.crit:backward(self.G, self.target)
dG:div(input:nElement())
self.gradInput = self.gram:backward(input, dG)
if self.normalize then
self.gradInput:div(torch.norm(self.gradInput, 1) + 1e-8)
end
self.gradInput:mul(self.strength)
self.gradInput:add(gradOutput)
return self.gradInput
end
function ExtractMask(seg, color)
local mask = nil
if color == 'green' then
mask = torch.lt(seg[1], 0.1)
mask:cmul(torch.gt(seg[2], 1-0.1))
mask:cmul(torch.lt(seg[3], 0.1))
elseif color == 'black' then
mask = torch.lt(seg[1], 0.1)
mask:cmul(torch.lt(seg[2], 0.1))
mask:cmul(torch.lt(seg[3], 0.1))
elseif color == 'white' then
mask = torch.gt(seg[1], 1-0.1)
mask:cmul(torch.gt(seg[2], 1-0.1))
mask:cmul(torch.gt(seg[3], 1-0.1))
elseif color == 'red' then
mask = torch.gt(seg[1], 1-0.1)
mask:cmul(torch.lt(seg[2], 0.1))
mask:cmul(torch.lt(seg[3], 0.1))
elseif color == 'blue' then
mask = torch.lt(seg[1], 0.1)
mask:cmul(torch.lt(seg[2], 0.1))
mask:cmul(torch.gt(seg[3], 1-0.1))
elseif color == 'yellow' then
mask = torch.gt(seg[1], 1-0.1)
mask:cmul(torch.gt(seg[2], 1-0.1))
mask:cmul(torch.lt(seg[3], 0.1))
elseif color == 'grey' then
mask = torch.cmul(torch.gt(seg[1], 0.5-0.1), torch.lt(seg[1], 0.5+0.1))
mask:cmul(torch.cmul(torch.gt(seg[2], 0.5-0.1), torch.lt(seg[2], 0.5+0.1)))
mask:cmul(torch.cmul(torch.gt(seg[3], 0.5-0.1), torch.lt(seg[3], 0.5+0.1)))
elseif color == 'lightblue' then
mask = torch.lt(seg[1], 0.1)
mask:cmul(torch.gt(seg[2], 1-0.1))
mask:cmul(torch.gt(seg[3], 1-0.1))
elseif color == 'purple' then
mask = torch.gt(seg[1], 1-0.1)
mask:cmul(torch.lt(seg[2], 0.1))
mask:cmul(torch.gt(seg[3], 1-0.1))
else
print('ExtractMask(): color not recognized, color = ', color)
end
return mask:float()
end
-- Define style loss with segmentation
local StyleLossWithSeg, parent = torch.class('nn.StyleLossWithSeg', 'nn.Module')
--function StyleLossWithSeg:__init(strength, target_grams, color_content_masks, content_seg_idxs, layer_id)
function StyleLossWithSeg:__init(strength, target_grams, color_content_masks, color_codes, layer_id)
parent.__init(self)
self.strength = strength
self.target_grams = target_grams
self.color_content_masks = deepcopy(color_content_masks)
self.color_codes = color_codes
--self.content_seg_idxs = content_seg_idxs
self.loss = 0
self.gram = GramMatrix()
self.crit = nn.MSECriterion()
self.layer_id = layer_id
end
function StyleLossWithSeg:updateOutput(input)
self.output = input
return self.output
end
function StyleLossWithSeg:updateGradInput(input, gradOutput)
self.loss = 0
self.gradInput = gradOutput:clone()
self.gradInput:zero()
for j = 1, #self.color_codes do
local l_content_mask_ori = self.color_content_masks[j]:clone():cuda()
local l_content_mask = l_content_mask_ori:repeatTensor(1,1,1):expandAs(input)
local l_content_mean = l_content_mask_ori:mean()
local masked_input_features = torch.cmul(l_content_mask, input)
local masked_input_gram = self.gram:forward(masked_input_features):clone()
if l_content_mean > 0 then
masked_input_gram:div(input:nElement() * l_content_mean)
end
local loss_j = self.crit:forward(masked_input_gram, self.target_grams[j])
loss_j = loss_j * self.strength * l_content_mean
self.loss = self.loss + loss_j
local dG = self.crit:backward(masked_input_gram, self.target_grams[j])
dG:div(input:nElement())
local gradient = self.gram:backward(masked_input_features, dG)
if self.normalize then
gradient:div(torch.norm(gradient, 1) + 1e-8)
end
self.gradInput:add(gradient)
end
self.gradInput:mul(self.strength)
self.gradInput:add(gradOutput)
return self.gradInput
end
local TVLoss, parent = torch.class('nn.TVLoss', 'nn.Module')
function TVLoss:__init(strength)
parent.__init(self)
self.strength = strength
self.x_diff = torch.Tensor()
self.y_diff = torch.Tensor()
end
function TVLoss:updateOutput(input)
self.output = input
return self.output
end
-- TV loss backward pass inspired by kaishengtai/neuralart
function TVLoss:updateGradInput(input, gradOutput)
self.gradInput:resizeAs(input):zero()
local C, H, W = input:size(1), input:size(2), input:size(3)
self.x_diff:resize(3, H - 1, W - 1)
self.y_diff:resize(3, H - 1, W - 1)
self.x_diff:copy(input[{{}, {1, -2}, {1, -2}}])
self.x_diff:add(-1, input[{{}, {1, -2}, {2, -1}}])
self.y_diff:copy(input[{{}, {1, -2}, {1, -2}}])
self.y_diff:add(-1, input[{{}, {2, -1}, {1, -2}}])
self.gradInput[{{}, {1, -2}, {1, -2}}]:add(self.x_diff):add(self.y_diff)
self.gradInput[{{}, {1, -2}, {2, -1}}]:add(-1, self.x_diff)
self.gradInput[{{}, {2, -1}, {1, -2}}]:add(-1, self.y_diff)
self.gradInput:mul(self.strength)
self.gradInput:add(gradOutput)
return self.gradInput
end
function TVGradient(input, gradOutput, strength)
local C, H, W = input:size(1), input:size(2), input:size(3)
local gradInput = torch.CudaTensor(C, H, W):zero()
local x_diff = torch.CudaTensor()
local y_diff = torch.CudaTensor()
x_diff:resize(3, H - 1, W - 1)
y_diff:resize(3, H - 1, W - 1)
x_diff:copy(input[{{}, {1, -2}, {1, -2}}])
x_diff:add(-1, input[{{}, {1, -2}, {2, -1}}])
y_diff:copy(input[{{}, {1, -2}, {1, -2}}])
y_diff:add(-1, input[{{}, {2, -1}, {1, -2}}])
gradInput[{{}, {1, -2}, {1, -2}}]:add(x_diff):add(y_diff)
gradInput[{{}, {1, -2}, {2, -1}}]:add(-1, x_diff)
gradInput[{{}, {2, -1}, {1, -2}}]:add(-1, y_diff)
gradInput:mul(strength)
gradInput:add(gradOutput)
return gradInput
end
local params = cmd:parse(arg)
main(params)