admincer 1.2.0

Description:

admincer 1.2.0

AdMincer
AdMincer is a command line tool for enriching datasets of screenshots used in
ML-based ad detection. It can probably be used with other object-detection
datasets, but ad detection is the main use case we're after.
Installation
Clone this repository, then:
$ cd admincer/
$ pip install .

Usage
From the command line, run $ admincer <command> to get information on command
options and usage. The current available options are place, extract,
slice, find, and convert.
Place
This command places fragment images into the regions of source images. It takes
a directory with source images that have regions marked on them and multiple
mappings of region type to fragment directory:
$ admincer place -f ad=ads/dir -f label=labels:other/labels -n 5 source target

This will take images with marked regions from source/, place images from
ads/dir/ into the regions of type ad and images from labels/ and
other/labels/ into the label regions. It will generate 5 images and store
them in target/.
The placements are performed in the order of region types on the command line.
In the example above first all ad regions will be placed and then all label
regions.
Region marking
Regions of the images can be defined via a CSV file in the following format
(the numbers are X and Y coordinates of the top left corner followed by the
bottom right corner, and the headings in the first line are required):
image,xmin,ymin,xmax,ymax,label
image1.png,50,50,80,90,region_type1
image2.gif,10,10,20,20,region_type2

They can also be defined via TXT files of the same name as the image. The TXT
files should be in the format commonly used with YOLO object detector. The
numbers are: <object-class> <x> <y> <width> <height>
Where:

<object-class> is an integer representing the box's label
<x> <y> are the float coordinates at the center of the rectangle
<width> <height> are the ratio of the box's width/height relative to the
size of the whole image, from (0.0 to 1.0].

E.g. <height> = <box_height> / <image_height>
0 0.075 0.15 0.05 0.1
1 0.225 0.15 0.05 0.1

It's possible to provide names for the region type numbers via placing a file
with .names extension into the directory. It should simply contian the names
in the successive lines:
region_type1
region_type2

When the names file is provided it's also possible to mix CSV and TXT region
definitions but not for the same image.
Note: regions that extend beyond the boundaries of the image will be clipped.
Resize modes
When the fragments placed into the regions are not of the same size as the
regions, there are several possible options for resizing them. The default
is to scale the fragment to match the size of the region. Another option is to
cut off the part of the fragment that doesn't fit and place the rest into the
part of the region that it would cover. Yet another approach is to cut off some
parts and pad the remaining image to the size of the region. These modes are
called scale, crop and pad respectively and they can be configured via
--resize-mode command line option. Example:
$ admincer place -f ad=ads/dir -f label=labels -r pad -r label=crop ...

Here the first -r sets the default resize mode and the second one overrides
it for label region type.
Extract
This command extracts the contents of marked regions from source images. It
takes a directory with source images with marked regions (see above) and
multiple mappings of region type to target directory:
$ admincer extract --target-dir ad=ads/dir -t label=labels source

This will load the images and region maps from source and will extract the
contents of the regions labeled ad and label into ads/dir and labels
directories respectively.
Slice
This command produces viewport-sized square screenshots from page-sized tall
rectangular screenshots. It remaps the regions of the original images to the
produced part (as long as sufficient part of the region is inside the part).
$ admincer slice --step=10 --min-part=50 source target

If additional --no-empty option is specified, slices that don't contain any
regions will not be produced.
Find
This command finds source images that have regions of specific types and sizes.
For example the following command will find all images in source directory
that have regions of the type ad 100 pixels wide by 50 pixels high.
$ admincer find --region=ad:100x50 source

There's certain tolerance for size mismatches. Normally it's +25% and -20%.
Tolerance can be configured via an additional parameter of the region query:
$ admincer find -r ad:100x50:100 source

Here height and width can be up to 100% larger and up to 50% smaller. In
general the tolerance value X allows the region to be X% larger than specified
or the specification to be X% larger than the region.
Multiple --region/-r options can be given. In this case images that contain
at least one region matching each query will be found (i.e. multiple queries
are combined using and operator).
Convert
This command will convert annotations from a CVAT-format .xml file into YOLO-
format .txt files, placing the .txt files alongside their images:
$ admincer convert source.xml

Multiple .xml files can also be provided, either as a list, or by using shell
expansions:
$ admincer convert *.xml

Optionally, a --target-dir can be specified. This will place the .txt
annotations into the specified target directory, along with a class.names
file indicating the <object-class> order. If no target-dir is given,
class.names will be written to the image directories.
$ admincer convert *.xml --target-dir path/to/target/

Additionally, the -m or -c flags may be given, which will either move or
copy the images to the --target-dir, respectively.
Notes:

Each image's name tag in the .xml file should contain the image's path,
relative to the xml file.
A .names file may be provided. If multiple image folders are combined into
a --target-dir, their .names files will be combined and written to
<target_dir>/class.names. If new labels are found, the .names file will
be overwritten to include all labels.

Questions

Fragment matching policy (current one allows scaling by 80% to 125%).
What to do if there are no valid candidate fragments for placement? Right now
we bomb out with an exception.
Do we want sampling with/without replacement? Or maybe some kind of
deterministic selection? Right now it's with replacement.