# Intel Media FFMPEG Transcode Container

This project hosts a container demonstrating the use of ffmpeg
using GPU offload for transcode operations.

# Using

Build the container:

```bash
docker build . -t intel-media-ffmpeg
```

Run the container:

```bash
docker run \
  --rm \
  --device=/dev/dri:/dev/dri \
  -it \
  intel-media-ffmpeg
```

## Developing

The Dockerfile itself is constructed from re-usable snippets,
located in the templates/ directory, and can be regenerated
by running:

```bash
scripts/build-dockerfile
```

The above script uses environment substitution to stamp version
information within the created Dockerfile. The files which declare
the environment variables are in **SOLUTION** and **MANIFEST**.

After joining the template/* pieces together, the file
**Dockerfile.solution** is then added to the Dockerfile with 
environment substitution.


## SOLUTION

Solution specific definitions:

    CONTAINER_IMAGE is used as the container tag name
    OS_DISTRO       is used as the base OS distribution. Possible values: ubuntu
    OS_RELEASE      is used as the OS version. Possible values: disco, eoan


## MANIFEST

The version of MANIFEST is created by the set of Agama packages from the Agama
repository and name-mangling them to be a VERSION declaration:

For example:

    libgl1-mesa-glx_19.0.1-agama-109_amd64.deb

is changed to:

    LIBGL1_MESA_GLX_VERSION=19.0.1-agama-109

The script you can use to recreate the OS_RELEASE defined in SOLUTION is:

NOTE: This only works on the Ubuntu releases.

```bash
AGAMA_VERSION=169
. SOLUTION
echo "AGAMA_VERSION=${AGAMA_VERSION}" > MANIFEST
wget -q -O - \
  https://osgc.jf.intel.com/packages/agama/ubuntu/dists/${OS_RELEASE}/main/binary-amd64/Packages.bz2 | 
    bunzip2 | 
    sed -nE 's/^(Package|Version): (.*)/\2/p' |
    paste -s -d' \n' |
    while read package version rest; do 
      package=$(echo $package | sed -E -e s#-#_#g -e 's#(.*)#\U\1#g')_VERSION
      echo $package=$version
    done | grep ${AGAMA_VERSION}\$ >> MANIFEST
```

This allows the Dockerfile templates to then version pin Agama packages:

```Dockerfile
  RUN apt-get install -y libgl1-mesa-glx=$LIBGL1_MESA_GLX_VERSION
```

The `scripts/build-dockerfile` loads MANIFEST, which defines
LIBGL1_MESA_GLX_VERSION. That is then subsituted for the version in
the above Dockerfile snippet when being placed into the main Dockerfile.

# Tagging

If the build succeeds, we want to be able to tag the git project
as well as corresponding Docker images with the appropriate Agama
tag:

```bash
. MANIFEST ; git tag -f agama-${AGAMA_VERSION}
```