media3/demos/transformer
huangdarwin ec6ed0d55f Demo: Add legacy external storage permission for intents.
Without this permission, files in `/sdcard` or other directories cannot be read by the demo, as they're not in the transformer demo's scoped storage container.

For more information, see https://developer.android.com/training/data-storage/use-cases

Tested by uninstalling and re-installing the demo app, granting permission by
starting a transformation, and launching an intent using a local file in `/sdcard`
to start another transformation. Without this CL, this threw an error, and with
this CL it succeeded.

PiperOrigin-RevId: 466399023
2022-09-30 16:26:28 +00:00
..

Transformer demo

This app demonstrates how to use the Transformer API to modify videos, for example by removing audio or video.

See the demos README for instructions on how to build and run this demo.

MediaPipe frame processing demo

Building the demo app with MediaPipe integration enabled requires some extra manual steps.

  1. Follow the instructions to install MediaPipe.

  2. Copy the Transformer demo's build configuration and MediaPipe graph text protocol buffer under the MediaPipe source tree. This makes it easy to build an AAR with bazel by reusing MediaPipe's workspace.

    cd "<path to MediaPipe checkout>"
    MEDIAPIPE_ROOT="$(pwd)"
    MEDIAPIPE_TRANSFORMER_ROOT="${MEDIAPIPE_ROOT}/mediapipe/java/com/google/mediapipe/transformer"
    cd "<path to the transformer demo (containing this readme)>"
    TRANSFORMER_DEMO_ROOT="$(pwd)"
    mkdir -p "${MEDIAPIPE_TRANSFORMER_ROOT}"
    mkdir -p "${TRANSFORMER_DEMO_ROOT}/libs"
    cp ${TRANSFORMER_DEMO_ROOT}/BUILD.bazel ${MEDIAPIPE_TRANSFORMER_ROOT}/BUILD
    cp ${TRANSFORMER_DEMO_ROOT}/src/withMediaPipe/assets/edge_detector_mediapipe_graph.pbtxt \
      ${MEDIAPIPE_TRANSFORMER_ROOT}
    
  3. Build the AAR and the binary proto for the demo's MediaPipe graph, then copy them to Transformer.

    cd ${MEDIAPIPE_ROOT}
    bazel build -c opt --strip=ALWAYS \
      --host_crosstool_top=@bazel_tools//tools/cpp:toolchain \
      --fat_apk_cpu=arm64-v8a,armeabi-v7a \
      --legacy_whole_archive=0 \
      --features=-legacy_whole_archive \
      --copt=-fvisibility=hidden \
      --copt=-ffunction-sections \
      --copt=-fdata-sections \
      --copt=-fstack-protector \
      --copt=-Oz \
      --copt=-fomit-frame-pointer \
      --copt=-DABSL_MIN_LOG_LEVEL=2 \
      --linkopt=-Wl,--gc-sections,--strip-all \
      mediapipe/java/com/google/mediapipe/transformer:edge_detector_mediapipe_aar.aar
    cp bazel-bin/mediapipe/java/com/google/mediapipe/transformer/edge_detector_mediapipe_aar.aar \
      ${TRANSFORMER_DEMO_ROOT}/libs
    bazel build mediapipe/java/com/google/mediapipe/transformer:edge_detector_binary_graph
    cp bazel-bin/mediapipe/java/com/google/mediapipe/transformer/edge_detector_mediapipe_graph.binarypb \
      ${TRANSFORMER_DEMO_ROOT}/src/withMediaPipe/assets
    
  4. In Android Studio, gradle sync and select the withMediaPipe build variant (this will only appear if the AAR is present), then build and run the demo app and select a MediaPipe-based effect.