header={
  "recipe_version": "1.13",
  "title": "Trim Video Black Detect",
  "description": "detect if the video has black frames at the beginning and remove them",
  "tags": "video",
  "chef": "BeatRig",
  "spice": "BQ==:G+Hy36kJcnQQYYavb/JV2Il6eCYr6h4hRJHCF9rRbhX5BcazL6cuTgUMdz0xA50VWA5PmmV0Q7aWkiUtNFtbk991l+t0e8IBXMReMIT1GNjnZZDv7n2YRAo0xcSQbY0ixjG6LLH4wGKnspKAoA/v69iLn6N2IH0XzIZwTGdHSo4=",
  "palette": "Clean Slate",
  "flavour": "exWHg9kyjzN6iWg9D9qSAfZ5TMR+hXYQUZgYzHNxPnlrQG29hkF/ABj8JeezKTv4Fb22dl85XNQGL7O1kgRTnxiZE4liFhSRys6Tu84j2cOUxowyrOc0MUb2Pje74M0HZkgwTflTdZJUlJwcTN24NbrAeHIZOuF6jvGnM1ZOGX0=",
  "time": 1674549224,
  "core_version": "0.4.0",
  "magnetron_version": "1.0.138",
  "dependencies": "ffprobe,ffmpeg",
  "type": "default",
  "os": "windows,macOS",
  "functions": "main",
  "uuid": "afc871158af44535830b64de1bc88dac",
  "instructions": "Drop file(s) here"
};



// =============================================================================
// GLOBALS
var framecount = 0;


// =============================================================================
function main()
{

    // MESSAGE
    setMainMessage("preparing");

    // CHECK VALID FILES
    validateInputFile();

    // GET ALL FILES
    var files = getFiles();

    // LOOP FILES
    for (i=0;i<files.length;i++)
    {

        // ---------------------------------------------------------------------
        //
        if(files[i].skip) break;

        //
        setMainMessage("preparing file");

        // INFILE
        var infile = files[i].path;

        // OUTFILE
        var path = getPathInfo(infile);


        // SET STATUS
        files[i]['file_icon'] = "CaretSquareORight";
        files[i]['file_status'] = 'processing';
        setFiles(files);

        // GETFRAMECOUNT FOR PROGRESS AND FRAMERATE
        ffprobe = cmd("ffprobe", [
            "-v","error",
            "-select_streams","v:0",
            "-count_packets",
            "-show_entries","stream=nb_read_packets,r_frame_rate,",
            "-of","csv=p=0",
            infile,
            ]);

        ffprobe = ffprobe.split(',');
        framecount = parseInt(ffprobe[1]);

        // ---------------------------------------------------------------------
        // DETECT BLACK
        setMainMessage("analyzing black frames");

        var blackDetect = cmd("ffprobe", [
            '-f','lavfi',
            '-i','movie='+infile+',blackdetect[out0]',
            '-show_entries','tags=lavfi.black_start,lavfi.black_end',
            '-of','default=nw=1',
            ]);

        var blackStart = parseFloat(searchRegEx(blackDetect, "(?:TAG:lavfi.black_start=)(.*?)(?=[\n\r])", "o", 1)[0]);
        var blackEnd = parseFloat(searchRegEx(blackDetect, "(?:TAG:lavfi.black_end=)(.*?)(?=[\n\r])", "o", 1)[0]);

        // ---------------------------------------------------------------------
        // OUTPUT FILE
        var vidout = path.folder+"/"+path.basename+"-[trimmed]."+path.ext;

        if(blackStart == 0. && blackEnd > 0.)
        {
            setMainMessage("trimming file");
            var ffmpeg = cmd("ffmpeg", [
                '-i',infile,
                '-ss',blackEnd,
                '-vcodec','copy',
                '-acodec','copy',
                vidout,
                '-y',
                ]);
        }

        // ---------------------------------------------------------------------
        // THIS FILE IS DONE
        setProgress(100);
        setMainMessage("file done");

        // SET STATUS
        files[i]['file_icon'] = "CheckSquare";
        files[i]['file_icon_color'] = "FF00aa00";
        files[i]['file_status'] = 'DONE';
        setFiles(files);

        // ---------------------------------------------------------------------
        }

    // ALL IS DONE
    setMainMessage("all done");
    }


// =============================================================================
function validateInputFile()
{
    var files = getFiles();
    var valid = [];

    setProgress(101);

    for (i=0;i<files.length;i++)
    {

        setMainMessage("preparing file "+i+" of "+files.length);

        var path = getPathInfo( files[i].path );

        // RUN FFPROBE TO GET STREAM TYPE TO CHECK IF IS ACVTUALLY A VIDEO
        var codec = cmd("ffprobe", [
            '-loglevel','error',
            '-show_entries','stream=codec_type',
            //'-of','csv=p=0',
            files[i].path,
            ]);


        var isVideo = searchRegEx(codec, "video", "i", 0).length > 0;
        valid.push({
            index: i,
            path: files[i].path,
            idpath: files[i].idpath,
            file_icon: (isVideo ? 'square' : 'Exclamation'),
            file_icon_color: (isVideo ? 'FFdddddd' : 'FFff0000'),
            file_status: (isVideo ? '' : 'Not a valid video file'),
            file_tooltip: '',
            skip: (isVideo ? false : true),
            });
    }

    // UPDATE FILES LIST
    setFiles(valid);
    setMainMessage("getting ready");

}



// =============================================================================
// FFMPEG PROCESS STATUS
function cmd_callback(cmd_name, cmd_output){
    if(cmd_name=="ffmpeg" && cmd_output.length > 0 && framecount > 0){
        var progress = searchRegEx(cmd_output, "(?:frame=)(.*?)(?:fps=)", "i", 1);
        progress = parseInt (progress[progress.length-1] );
        progress = Math.round( progress/framecount* 100 );
        setProgress(progress);
        setMainMessage("processing "+progress+"%");
        }
    }