Runtime environment

1. macOS / Linux / Windows

2. Java 17/11 LTS

   1. On macOS, SDKMAN! can be used to install one

       sdk install java 17.0.4-amzn
      

Build environment

In addition to the runtime environment

1. SBT 1.7.1

   1. On macOS, SDKMAN! can be used to install one

       sdk install sbt
      

   2. On Windows MSI installer

      1. It might be older version but the correct version is automatically downloaded and used

How to build and run

Building and running locally

Start sbt

1. Build and run the tool

    tool/run
   

   1. Examples

       tool/run verify -in ../evip/out/ESA.pdf
      

2. Build the fat jar for distribution

    tool/assembly
   

   1. To run locally

       java -jar tool/target/scala-3.1.3/tool-assembly-0.1.0.jar
      

The program

The program to run is constructed by

1. The following imports are inserted at the beginning

    import java.nio.file._
    import scala.util._
    import scala.util.Properties.{userHome => HOME, userName => USER}
    import cats._
    import cats.syntax.all._
    import cats.effect._
    import cats.effect.syntax._
    import fs2._
   
    import jp.ken1ma.ffmpeg.FFmpegStream
    val ffmpegStream = FFmpegStream[IO]
    import ffmpegStream._
   

2. -i and -o are translated into value definitions

   1. --in=text will be in = Path.of(s"$text")
   2. --out=text will be out = Path.of(s"$text")

3. -e is is a raw Scala expression, except

   1. name = value becomes val name = value

      1. When it starts with name =, val is inserted at the beginning

   2. TODO: expr { name =>

   3. TODO: Multiple expressions will be connected by flatMap?

Examples

1. Extract video frames

   1. All the frames as JPEG files

       tool/run run -i "$HOME/Downloads/Record of Lodoss War Opening [HD]-kagzOJsHBg4.mp4" -o "out/Lodoss-allFrames" -e "readFile(in).flatMap { fmtCtx =>" -e "stream = fmtCtx.videoStreams.head" -e "FrameFileGen.jpeg(dir = out, stream.width, stream.height).flatMap { fileGen =>" -e "streamFrames(stream, fmtCtx).map(_.frm).flatMap(fileGen)" --show-scala
      

   2. The key frames as PNG files

       tool/run run -i "$HOME/Downloads/Record of Lodoss War Opening [HD]-kagzOJsHBg4.mp4" -o "out/Lodoss-keyFrames" -e "readFile(in, dump = true).flatMap { fmtCtx =>" -e "stream = fmtCtx.videoStreams.head" -e "FrameFileGen.png(dir = out, stream.width, stream.height).flatMap { fileGen =>" -e "streamFrames(stream, fmtCtx).map(_.frm).filter(_.keyFrame).flatMap(fileGen)" --show-scala
      

2. Transcode a video to H264

    tool/run run -i "$HOME/Downloads/Record of Lodoss War Opening [HD]-kagzOJsHBg4.mp4" -o "out/Lodoss.h264" -e "readFile(in).flatMap { fmtCtx =>" -e "stream = fmtCtx.videoStreams.head" -e "FileWrite.h264(out, stream.width, stream.height).flatMap { fileWrite =>" -e "streamFrames(stream, fmtCtx).map(_.frm).flatMap(fileWrite)" --show-scala
   

   1. Skip even frames (frame_number starts at 1)

       tool/run run -i "$HOME/Downloads/Record of Lodoss War Opening [HD]-kagzOJsHBg4.mp4" -o "out/Lodoss-oddFrames.h264" -e "readFile(in).flatMap { fmtCtx =>" -e "stream = fmtCtx.videoStreams.head" -e "FileWrite.h264(out, stream.width, stream.height).flatMap { fileWrite =>" -e "streamFrames(stream, fmtCtx).filter(_.decodeCtx.codec_ctx.frame_number % 2 == 1).map(_.frm).flatMap(fileWrite)" --show-scala
      

   2. Halve the dimension by swscale

       tool/run run -i "$HOME/Downloads/Record of Lodoss War Opening [HD]-kagzOJsHBg4.mp4" -o "out/Lodoss-scaled.h264" -e "readFile(in).flatMap { fmtCtx =>" -e "stream = fmtCtx.videoStreams.head" -e "FileWrite.h264(out, stream.width / 2, stream.height / 2).flatMap { fileWrite =>" -e "allocSwScaleContextWithDstFrm(stream.width, stream.height, AV_PIX_FMT_YUV420P, stream.width / 2, stream.height / 2, AV_PIX_FMT_YUV420P, logCtx = fmtCtx).flatMap { swScaleCtx =>" -e "streamFrames(stream, fmtCtx).map(_.frm).flatMap(srcFrm => scaleFrame(srcFrm, swScaleCtx)).flatMap(_ => fileWrite(swScaleCtx.dstFrm))" --show-scala
      

   3. Halve the dimension by filter, add time text, only even frames

       tool/run run -i "$HOME/Downloads/Record of Lodoss War Opening [HD]-kagzOJsHBg4.mp4" -o "out/Lodoss-filtered.h264" -e "timeOffset = Instant.now.getEpochSecond" -e "readFile(in).flatMap { fmtCtx =>" -e "stream = fmtCtx.videoStreams.head" -e "FileWrite.h264(out, stream.width / 2, stream.height / 2).flatMap { fileWrite =>" -e "allocFilter(s\\u0022scale=\${stream.width / 2}:\${stream.height / 2},drawtext=text='%{pts\\\\\\\\:localtime\\\\\\\\:\\u0022 + timeOffset + \\u0022\\\\\\\\:%Y/%m/%d %T}':fontfile=data/font/ipaexg.ttf:fontsize=20:fontcolor=red:x=w-tw-10:y=h-th-10\\u0022, stream.width, stream.height, AV_PIX_FMT_YUV420P, stream.time_base.num, stream.time_base.den, stream.sample_aspect_ratio.num, stream.sample_aspect_ratio.den, parentLogCtx = fmtCtx).flatMap { filterCtx =>" -e "streamFrames(stream, fmtCtx).filter(_.decodeCtx.codec_ctx.frame_number % 2 == 1).map(_.frm).flatMap(srcFrm => filterCtx.filterFrame(srcFrm, fileWrite))" --show-scala
      

      1. The unescaped drawText is drawtext=text='%{pts\\:localtime\\:" + timeOffset + "\\:%Y/%m/%d %T}'

3. Transcode an audio to aac

    tool/run run -i "$HOME/Documents/convivial/Moomin.wav" -o "out/Moomin.aac" -e "readFile(in).flatMap { fmtCtx =>" -e "stream = fmtCtx.audioStreams.head" -e "FileWrite.aac(out, stream).flatMap { fileWrite =>" -e "streamFrames(stream, fmtCtx).flatMap(fileWrite)"
   

More SBT commands

1. Run the unit tests

    test
   

2. Delete the built files

    clean
   

3. Search for dependency updates

    dependencyUpdates
   

4. Show the dependencies

    dependencyTree
   

References

1. https://github.com/FFmpeg/FFmpeg/blob/master/doc/examples/
2. https://ffmpeg.org/doxygen/5.0/
3. https://javadoc.io/doc/org.bytedeco/javacpp/latest/index.html
4. https://javadoc.io/doc/org.bytedeco/ffmpeg/latest/index.html
5. https://www.ffmpeg.org/ffmpeg-filters.html#drawtext-1