Tools

Here is a list of online tools you may find useful.

Hi

I am David Corvoysier, versatile developer and open Source enthusiast.

Explore Tensorflow features with the CIFAR10 dataset

26 Jun 2017 by David Corvoysier

The reason I started using Tensorflow was because of the limitations of my experiments so far, where I had coded my models from scratch following the guidance of the CNN for visual recognition course.

I already knew how CNN worked, and had already a good experience of what it takes to train a good model. I had also read a lot of papers presenting multiple variations of CNN topologies, those aiming at increasing accuracy like those aiming at reducing model complexity and size.

I work in the embedded world, so performance is obviously one of my primary concern, but I soon realized that the CNN state of the art for computer vision had not reached a consensus yet on the best compromise between accuracy and performance.

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Build and boot a minimal Linux system with qemu

23 Sep 2016 by David Corvoysier

When you want to build a Linux system for an embedded target these days, it is very unlikely that you decide to do it from scratch.

Embedded Linux build systems are really smart and efficients, and will fit almost all use cases: should you need only a simple system, buildroot should be your first choice, and if you want to include more advanced features, or even create a full distribution, Yocto is the way to go.

That said, even if these tools will do all the heavy-lifting for you, they are not perfect, and if you are using less common configurations, you may stumble upon issues that were not expected. In that case, it may be important to understand what happens behind the scenes.

In this post, I will describe step-by-step how you can build a minimal Linux system for an embedded target and boot it using QEMU.

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Benchmarking build systems for a large C project

01 Sep 2016 by David Corvoysier

The performance of build systems has been discussed at large in the developer community, with a strong emphasis made on the limitations of the legacy Make tool when dealing with large/complex projects.

I recently had to develop a build-system to create firmwares for embedded targets from more than 1000 source files.

The requirements were to use build recipes that could be customized for each directory and file in the source tree, similar to what the Linux Kernel does with kbuild.

I designed a custom recursive Make solution inspired by kbuild.

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Decentralized modules declarations in C using ELF sections

17 Aug 2016 by David Corvoysier

In modular programming, a standard practice is to define common interfaces allowing the same type of operation to be performed on a set of otherwise independent modules.


modules = [a,b,...]

for each m in modules:
    m.foo
    m.bar

To implement this pattern, two mechanisms are required:

instantiation, to allow each module to define an ‘instance’ of the common interface,
registration, to allow each module to ‘provide’ this instance to other modules.

Instantiation is typically supported natively in high-level languages.

Registration is more difficult and usually requires specific code to be written, or relying on external frameworks.

Let’s see how these two mechanisms can be implemented for C programs.

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