Merge pull request #10524 from marmelab/CI/check_videod_chromasubsamp…

…ling

Check videos "Chroma Subsampling" on CI check and explain how to fix a bad encoding

scripts/check-documentation-videos-format.sh

@@ -1,13 +1,46 @@
-for file in ./docs/img/**; do
-  codec=$(mediainfo --Inform="Video;%CodecID%" "$file")
+checkCodecId() {
+  codec=$(mediainfo --Inform="Video;%CodecID%" "$1")
+
   if [ "$codec" = "hvc1" ]; then
     # Construct the output file name
-    output_file="${file%.*}_avc1.${file##*.}"
-    echo "Invalid codec for $file"
+    output_file="${1%.*}_avc1.${1##*.}"
+    echo "Invalid codec for $1"
     echo "Convert it to avc1 with:"
-    echo "ffmpeg -i $file -c:v libx264 -c:a copy ${output_file}"
-    echo "rm $file"
-    echo "mv $output_file $file"
-    exit 1;
+    echo "ffmpeg -i $1 -c:v libx264 -c:a copy ${output_file}"
+    echo "rm $1"
+    echo "mv $output_file $1"
+    exit 1
+  fi
+
+}
+
+checkChromaSubsampling() {
+  imageencode=$(mediainfo --Inform="Video;%ChromaSubsampling%" "$1")
+
+  if [ "$imageencode" = "4:4:4" ]; then
+    # Construct the output file name
+    output_file="${1%.*}_420.${1##*.}"
+    echo "\nInvalid ChromaSubsampling for $1"
+
+    echo "\nConvert it to yuv420p with:"
+    case $2 in
+    "mp4") echo "ffmpeg -i ${1} -c:v libx264 -pix_fmt yuv420p -c:a copy ${output_file}" ;;
+    "webm") echo "ffmpeg -i ${1} -c:v libvpx-vp9 -pix_fmt yuv420p -c:a libopus -b:a 128k ${output_file}" ;;
+    esac
+
+    echo "\nThen replace the file with:"
+    echo "rm $1 && mv $output_file $1\n"
+    exit 1
   fi
-done
+
+}
+
+for file in ./docs/img/**; do
+  checkCodecId $file
+
+  case "$file" in
+  *.mp4) checkChromaSubsampling $file "mp4" ;;
+  *.webm) checkChromaSubsampling $file "webm" ;;
+  esac
+
+done