add better check for interlaced content (#2620)

CHANGELOG.md

@@ -31,6 +31,11 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
     - AviSynth itself needs to be installed
 - Add `Troubleshoot` button to classic schedule list
   - This generates JSON representing the entire schedule which can be shared when requested for troubleshooting
+- Add **Settings** > **FFmpeg** > **Probe For Interlaced Frames**
+  - When enabled, this will probe *local content* for interlaced frames on demand (immediately before playback)
+  - This will be used as a more accurate check for interlaced content
+  - The result will be cached (only probed once and stored) in the database along with all other media item statistics (e.g. duration)
+  - This feature will currently ignore content that is not streamed from disk
 
 ### Fixed
 - Fix HLS Direct playback with Jellyfin 10.11

ErsatzTV.Application/FFmpegProfiles/Commands/UpdateFFmpegSettingsHandler.cs

@@ -113,6 +113,11 @@ public class UpdateFFmpegSettingsHandler(
             await workerChannel.WriteAsync(new ExtractEmbeddedSubtitles(Option<int>.None), cancellationToken);
         }
 
+        await configElementRepository.Upsert(
+            ConfigElementKey.FFmpegProbeForInterlacedFrames,
+            request.Settings.ProbeForInterlacedFrames,
+            cancellationToken);
+
         if (request.Settings.GlobalWatermarkId is not null)
         {
             await configElementRepository.Upsert(

ErsatzTV.Application/FFmpegProfiles/FFmpegSettingsViewModel.cs

@@ -10,6 +10,7 @@ public class FFmpegSettingsViewModel
     public string PreferredAudioLanguageCode { get; set; }
     public bool UseEmbeddedSubtitles { get; set; }
     public bool ExtractEmbeddedSubtitles { get; set; }
+    public bool ProbeForInterlacedFrames { get; set; }
     public bool SaveReports { get; set; }
     public int? GlobalWatermarkId { get; set; }
     public int? GlobalFallbackFillerId { get; set; }

ErsatzTV.Application/FFmpegProfiles/Queries/GetFFmpegSettingsHandler.cs

@@ -33,6 +33,10 @@ public class GetFFmpegSettingsHandler(IConfigElementRepository configElementRepo
             await configElementRepository.GetValue<bool>(
                 ConfigElementKey.FFmpegExtractEmbeddedSubtitles,
                 cancellationToken);
+        Option<bool> probeForInterlacedFrames =
+            await configElementRepository.GetValue<bool>(
+                ConfigElementKey.FFmpegProbeForInterlacedFrames,
+                cancellationToken);
         Option<int> watermark =
             await configElementRepository.GetValue<int>(ConfigElementKey.FFmpegGlobalWatermarkId, cancellationToken);
         Option<int> fallbackFiller =
@@ -62,6 +66,7 @@ public class GetFFmpegSettingsHandler(IConfigElementRepository configElementRepo
             SaveReports = await saveReports.IfNoneAsync(false),
             UseEmbeddedSubtitles = await useEmbeddedSubtitles.IfNoneAsync(true),
             ExtractEmbeddedSubtitles = await extractEmbeddedSubtitles.IfNoneAsync(false),
+            ProbeForInterlacedFrames = await probeForInterlacedFrames.IfNoneAsync(false),
             PreferredAudioLanguageCode = await preferredAudioLanguageCode.IfNoneAsync("eng"),
             HlsSegmenterIdleTimeout = await hlsSegmenterIdleTimeout.IfNoneAsync(60),
             WorkAheadSegmenterLimit = await workAheadSegmenterLimit.IfNoneAsync(1),

ErsatzTV.Application/Streaming/Queries/GetPlayoutItemProcessByChannelNumberHandler.cs

@@ -408,7 +408,7 @@ public class GetPlayoutItemProcessByChannelNumberHandler : FFmpegProcessHandler<
                 ffprobePath,
                 saveReports,
                 channel,
-                videoVersion,
+                new MediaItemVideoVersion(playoutItemWithPath.PlayoutItem.MediaItem, videoVersion),
                 new MediaItemAudioVersion(playoutItemWithPath.PlayoutItem.MediaItem, audioVersion),
                 videoPath,
                 audioPath,

ErsatzTV.Application/Troubleshooting/Commands/PrepareTroubleshootingPlaybackHandler.cs

@@ -224,7 +224,7 @@ public class PrepareTroubleshootingPlaybackHandler(
             ffprobePath,
             true,
             channel,
-            videoVersion,
+            new MediaItemVideoVersion(mediaItem, videoVersion),
             new MediaItemAudioVersion(mediaItem, version),
             videoPath,
             mediaPath,

ErsatzTV.Core/Domain/ConfigElementKey.cs

@@ -19,6 +19,7 @@ public class ConfigElementKey
     public static ConfigElementKey FFmpegSaveReports => new("ffmpeg.save_reports");
     public static ConfigElementKey FFmpegUseEmbeddedSubtitles => new("ffmpeg.use_embedded_subtitles");
     public static ConfigElementKey FFmpegExtractEmbeddedSubtitles => new("ffmpeg.extract_embedded_subtitles");
+    public static ConfigElementKey FFmpegProbeForInterlacedFrames => new("ffmpeg.probe_for_interlaced_frames");
     public static ConfigElementKey FFmpegPreferredLanguageCode => new("ffmpeg.preferred_language_code");
     public static ConfigElementKey FFmpegGlobalWatermarkId => new("ffmpeg.global_watermark_id");
     public static ConfigElementKey FFmpegGlobalFallbackFillerId => new("ffmpeg.global_fallback_filler_id");

ErsatzTV.Core/Domain/MediaItem/MediaVersion.cs

@@ -14,6 +14,7 @@ public class MediaVersion : IDisplaySize
     public string DisplayAspectRatio { get; set; }
     public string RFrameRate { get; set; }
     public VideoScanKind VideoScanKind { get; set; }
+    public double? InterlacedRatio { get; set; }
     public DateTime DateAdded { get; set; }
     public DateTime DateUpdated { get; set; }
     public int Width { get; set; }

ErsatzTV.Core/FFmpeg/FFmpegLibraryProcessService.cs

@@ -4,7 +4,9 @@ using CliWrap;
 using CliWrap.Buffered;
 using ErsatzTV.Core.Domain;
 using ErsatzTV.Core.Domain.Filler;
+using ErsatzTV.Core.Extensions;
 using ErsatzTV.Core.Interfaces.FFmpeg;
+using ErsatzTV.Core.Interfaces.Metadata;
 using ErsatzTV.Core.Interfaces.Repositories;
 using ErsatzTV.Core.Interfaces.Streaming;
 using ErsatzTV.FFmpeg;
@@ -26,6 +28,8 @@ public class FFmpegLibraryProcessService : IFFmpegProcessService
     private readonly IGraphicsElementLoader _graphicsElementLoader;
     private readonly IMemoryCache _memoryCache;
     private readonly IMpegTsScriptService _mpegTsScriptService;
+    private readonly ILocalStatisticsProvider _localStatisticsProvider;
+    private readonly IMediaItemRepository _mediaItemRepository;
     private readonly ICustomStreamSelector _customStreamSelector;
     private readonly FFmpegProcessService _ffmpegProcessService;
     private readonly IFFmpegStreamSelector _ffmpegStreamSelector;
@@ -43,6 +47,8 @@ public class FFmpegLibraryProcessService : IFFmpegProcessService
         IGraphicsElementLoader graphicsElementLoader,
         IMemoryCache memoryCache,
         IMpegTsScriptService mpegTsScriptService,
+        ILocalStatisticsProvider localStatisticsProvider,
+        IMediaItemRepository mediaItemRepository,
         ILogger<FFmpegLibraryProcessService> logger)
     {
         _ffmpegProcessService = ffmpegProcessService;
@@ -54,6 +60,8 @@ public class FFmpegLibraryProcessService : IFFmpegProcessService
         _graphicsElementLoader = graphicsElementLoader;
         _memoryCache = memoryCache;
         _mpegTsScriptService = mpegTsScriptService;
+        _localStatisticsProvider = localStatisticsProvider;
+        _mediaItemRepository = mediaItemRepository;
         _logger = logger;
     }
 
@@ -62,7 +70,7 @@ public class FFmpegLibraryProcessService : IFFmpegProcessService
         string ffprobePath,
         bool saveReports,
         Channel channel,
-        MediaVersion videoVersion,
+        MediaItemVideoVersion videoVersion,
         MediaItemAudioVersion audioVersion,
         string videoPath,
         string audioPath,
@@ -92,7 +100,7 @@ public class FFmpegLibraryProcessService : IFFmpegProcessService
         bool canProxy,
         CancellationToken cancellationToken)
     {
-        MediaStream videoStream = await _ffmpegStreamSelector.SelectVideoStream(videoVersion);
+        MediaStream videoStream = await _ffmpegStreamSelector.SelectVideoStream(videoVersion.MediaVersion);
 
         // we cannot burst live input
         hlsRealtime = hlsRealtime || streamInputKind is StreamInputKind.Live;
@@ -100,7 +108,7 @@ public class FFmpegLibraryProcessService : IFFmpegProcessService
         FFmpegPlaybackSettings playbackSettings = FFmpegPlaybackSettingsCalculator.CalculateSettings(
             channel.StreamingMode,
             channel.FFmpegProfile,
-            videoVersion,
+            videoVersion.MediaVersion,
             videoStream,
             start,
             now,
@@ -214,6 +222,8 @@ public class FFmpegLibraryProcessService : IFFmpegProcessService
                 };
             });
 
+        ScanKind scanKind = await ProbeScanKind(ffmpegPath, videoVersion.MediaItem, cancellationToken);
+
         var ffmpegVideoStream = new VideoStream(
             videoStream.Index,
             videoStream.Codec,
@@ -224,12 +234,12 @@ public class FFmpegLibraryProcessService : IFFmpegProcessService
                 videoStream.ColorSpace,
                 videoStream.ColorTransfer,
                 videoStream.ColorPrimaries),
-            new FrameSize(videoVersion.Width, videoVersion.Height),
-            videoVersion.SampleAspectRatio,
-            videoVersion.DisplayAspectRatio,
-            videoVersion.RFrameRate,
+            new FrameSize(videoVersion.MediaVersion.Width, videoVersion.MediaVersion.Height),
+            videoVersion.MediaVersion.SampleAspectRatio,
+            videoVersion.MediaVersion.DisplayAspectRatio,
+            videoVersion.MediaVersion.RFrameRate,
             videoPath != audioPath, // still image when paths are different
-            videoVersion.VideoScanKind == VideoScanKind.Progressive ? ScanKind.Progressive : ScanKind.Interlaced);
+            scanKind);
 
         var videoInputFile = new VideoInputFile(
             videoPath,
@@ -455,8 +465,8 @@ public class FFmpegLibraryProcessService : IFFmpegProcessService
 
         if (channel.FFmpegProfile.ScalingBehavior is ScalingBehavior.Crop)
         {
-            bool isTooSmallToCrop = videoVersion.Height < channel.FFmpegProfile.Resolution.Height ||
-                                    videoVersion.Width < channel.FFmpegProfile.Resolution.Width;
+            bool isTooSmallToCrop = videoVersion.MediaVersion.Height < channel.FFmpegProfile.Resolution.Height ||
+                                    videoVersion.MediaVersion.Width < channel.FFmpegProfile.Resolution.Width;
 
             // if any dimension is smaller than the crop, scale beyond the crop (beyond the target resolution)
             if (isTooSmallToCrop)
@@ -546,7 +556,7 @@ public class FFmpegLibraryProcessService : IFFmpegProcessService
             ptsOffset,
             playbackSettings.ThreadCount,
             qsvExtraHardwareFrames,
-            videoVersion is BackgroundImageMediaVersion { IsSongWithProgress: true },
+            videoVersion.MediaVersion is BackgroundImageMediaVersion { IsSongWithProgress: true },
             false,
             GetTonemapAlgorithm(playbackSettings),
             channel.UniqueId == Guid.Empty);
@@ -584,6 +594,47 @@ public class FFmpegLibraryProcessService : IFFmpegProcessService
         return new PlayoutItemResult(command, graphicsEngineContext);
     }
 
+    private async Task<ScanKind> ProbeScanKind(
+        string ffmpegPath,
+        MediaItem mediaItem,
+        CancellationToken cancellationToken)
+    {
+        var headVersion = mediaItem.GetHeadVersion();
+        if (headVersion.VideoScanKind is VideoScanKind.Interlaced)
+        {
+            _logger.LogDebug("Container is marked {ScanKind}", headVersion.VideoScanKind);
+            return ScanKind.Interlaced;
+        }
+
+        // skip probe if disabled
+        if (!await _configElementRepository.GetValue<bool>(
+                ConfigElementKey.FFmpegProbeForInterlacedFrames,
+                cancellationToken).IfNoneAsync(false))
+        {
+            _logger.LogDebug("Probe for interlaced frames is disabled");
+            return ScanKind.Progressive;
+        }
+
+        if (headVersion.InterlacedRatio is null)
+        {
+            _logger.LogDebug("Will probe for interlaced frames");
+
+            Option<double> maybeInterlacedRatio =
+                await _localStatisticsProvider.GetInterlacedRatio(ffmpegPath, mediaItem, cancellationToken);
+            foreach (double ratio in maybeInterlacedRatio)
+            {
+                await _mediaItemRepository.SetInterlacedRatio(mediaItem, ratio);
+            }
+        }
+
+        var result = headVersion.InterlacedRatio > 0.05 ? ScanKind.Interlaced : ScanKind.Progressive;
+        _logger.LogDebug(
+            "Content has interlaced ratio of {Ratio} - will consider as {ScanKind}",
+            headVersion.InterlacedRatio,
+            result);
+        return result;
+    }
+
     public async Task<Command> ForError(
         string ffmpegPath,
         Channel channel,
@@ -847,7 +898,7 @@ public class FFmpegLibraryProcessService : IFFmpegProcessService
         // TODO: save reports?
         string defaultScript = await _configElementRepository
             .GetValue<string>(ConfigElementKey.FFmpegDefaultMpegTsScript, cancellationToken)
-            .IfNoneAsync("default");
+            .IfNoneAsync("Default");
         List<MpegTsScript> allScripts = _mpegTsScriptService.GetScripts();
         Option<MpegTsScript> maybeScript = Optional(allScripts.Find(s => s.Id == defaultScript));
         foreach (var script in maybeScript)

ErsatzTV.Core/FFmpeg/MediaItemVideoVersion.cs

@@ -0,0 +1,5 @@
+using ErsatzTV.Core.Domain;
+
+namespace ErsatzTV.Core.FFmpeg;
+
+public record MediaItemVideoVersion(MediaItem MediaItem, MediaVersion MediaVersion);

ErsatzTV.Core/Interfaces/FFmpeg/IFFmpegProcessService.cs

@@ -14,7 +14,7 @@ public interface IFFmpegProcessService
         string ffprobePath,
         bool saveReports,
         Channel channel,
-        MediaVersion videoVersion,
+        MediaItemVideoVersion videoVersion,
         MediaItemAudioVersion audioVersion,
         string videoPath,
         string audioPath,

ErsatzTV.Core/Interfaces/Metadata/ILocalStatisticsProvider.cs

@@ -9,4 +9,9 @@ public interface ILocalStatisticsProvider
     Task<Either<BaseError, bool>> RefreshStatistics(string ffmpegPath, string ffprobePath, MediaItem mediaItem);
 
     Either<BaseError, List<SongTag>> GetSongTags(MediaItem mediaItem);
+
+    Task<Option<double>> GetInterlacedRatio(
+        string ffmpegPath,
+        MediaItem mediaItem,
+        CancellationToken cancellationToken);
 }

ErsatzTV.Core/Interfaces/Repositories/IMediaItemRepository.cs

@@ -13,4 +13,5 @@ public interface IMediaItemRepository
     Task<Unit> FlagNormal(MediaItem mediaItem);
     Task<Either<BaseError, Unit>> DeleteItems(List<int> mediaItemIds);
     Task<ImmutableHashSet<string>> GetAllTrashedItems(LibraryPath libraryPath);
+    Task SetInterlacedRatio(MediaItem mediaItem, double interlacedRatio);
 }

ErsatzTV.Infrastructure.MySql/Migrations/20251110043500_Add_MediaVersionInterlacedRatio.cs

@@ -0,0 +1,28 @@
+using Microsoft.EntityFrameworkCore.Migrations;
+
+#nullable disable
+
+namespace ErsatzTV.Infrastructure.MySql.Migrations
+{
+    /// <inheritdoc />
+    public partial class Add_MediaVersionInterlacedRatio : Migration
+    {
+        /// <inheritdoc />
+        protected override void Up(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.AddColumn<double>(
+                name: "InterlacedRatio",
+                table: "MediaVersion",
+                type: "double",
+                nullable: true);
+        }
+
+        /// <inheritdoc />
+        protected override void Down(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.DropColumn(
+                name: "InterlacedRatio",
+                table: "MediaVersion");
+        }
+    }
+}

ErsatzTV.Infrastructure.MySql/Migrations/TvContextModelSnapshot.cs

@@ -1393,6 +1393,9 @@ namespace ErsatzTV.Infrastructure.MySql.Migrations
                     b.Property<int?>("ImageId")
                         .HasColumnType("int");
 
+                    b.Property<double?>("InterlacedRatio")
+                        .HasColumnType("double");
+
                     b.Property<int?>("MovieId")
                         .HasColumnType("int");
 

ErsatzTV.Infrastructure.Sqlite/Migrations/20251110043425_Add_MediaVersionInterlacedRatio.cs

@@ -0,0 +1,28 @@
+using Microsoft.EntityFrameworkCore.Migrations;
+
+#nullable disable
+
+namespace ErsatzTV.Infrastructure.Sqlite.Migrations
+{
+    /// <inheritdoc />
+    public partial class Add_MediaVersionInterlacedRatio : Migration
+    {
+        /// <inheritdoc />
+        protected override void Up(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.AddColumn<double>(
+                name: "InterlacedRatio",
+                table: "MediaVersion",
+                type: "REAL",
+                nullable: true);
+        }
+
+        /// <inheritdoc />
+        protected override void Down(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.DropColumn(
+                name: "InterlacedRatio",
+                table: "MediaVersion");
+        }
+    }
+}

ErsatzTV.Infrastructure.Sqlite/Migrations/TvContextModelSnapshot.cs

@@ -1326,6 +1326,9 @@ namespace ErsatzTV.Infrastructure.Sqlite.Migrations
                     b.Property<int?>("ImageId")
                         .HasColumnType("INTEGER");
 
+                    b.Property<double?>("InterlacedRatio")
+                        .HasColumnType("REAL");
+
                     b.Property<int?>("MovieId")
                         .HasColumnType("INTEGER");
 

ErsatzTV.Infrastructure/Data/Repositories/MediaItemRepository.cs

@@ -112,6 +112,18 @@ public class MediaItemRepository : IMediaItemRepository
             .Map(list => list.ToImmutableHashSet());
     }
 
+    public async Task SetInterlacedRatio(MediaItem mediaItem, double interlacedRatio)
+    {
+        await using TvContext dbContext = await _dbContextFactory.CreateDbContextAsync();
+
+        var mediaVersion = mediaItem.GetHeadVersion();
+        mediaVersion.InterlacedRatio = interlacedRatio;
+
+        await dbContext.Connection.ExecuteAsync(
+            @"UPDATE MediaVersion SET InterlacedRatio = @InterlacedRatio WHERE Id = @Id",
+            new { mediaVersion.Id, InterlacedRatio = interlacedRatio });
+    }
+
     public async Task<Unit> FlagNormal(MediaItem mediaItem)
     {
         await using TvContext dbContext = await _dbContextFactory.CreateDbContextAsync();

ErsatzTV.Infrastructure/Data/Repositories/MetadataRepository.cs

@@ -137,6 +137,7 @@ public class MetadataRepository(IDbContextFactory<TvContext> dbContextFactory) :
                     existing.Width = incoming.Width;
                     existing.Height = incoming.Height;
                     existing.VideoScanKind = incoming.VideoScanKind;
+                    existing.InterlacedRatio = incoming.InterlacedRatio;
                     existing.RFrameRate = incoming.RFrameRate;
                 }
 

ErsatzTV.Infrastructure/Metadata/LocalStatisticsProvider.cs

@@ -18,7 +18,7 @@ using File = TagLib.File;
 
 namespace ErsatzTV.Infrastructure.Metadata;
 
-public class LocalStatisticsProvider : ILocalStatisticsProvider
+public partial class LocalStatisticsProvider : ILocalStatisticsProvider
 {
     private readonly IClient _client;
     private readonly IHardwareCapabilitiesFactory _hardwareCapabilitiesFactory;
@@ -131,6 +131,52 @@ public class LocalStatisticsProvider : ILocalStatisticsProvider
         }
     }
 
+    public async Task<Option<double>> GetInterlacedRatio(
+        string ffmpegPath,
+        MediaItem mediaItem,
+        CancellationToken cancellationToken)
+    {
+        try
+        {
+            string filePath = await PathForMediaItem(mediaItem);
+
+            if (Path.GetExtension(filePath) == ".avs" && !_hardwareCapabilitiesFactory.IsAviSynthInstalled())
+            {
+                return Option<double>.None;
+            }
+
+            if (filePath.StartsWith("http", StringComparison.OrdinalIgnoreCase) ||
+                !_localFileSystem.FileExists(filePath))
+            {
+                _logger.LogDebug("Skipping interlaced ratio check for remote content");
+                return Option<double>.None;
+            }
+
+            var duration = mediaItem.GetDurationForPlayout();
+            if (duration < TimeSpan.FromSeconds(3))
+            {
+                return Option<double>.None;
+            }
+
+            Option<IdetStatistics> maybeStats = await GetIdetOutput(ffmpegPath, filePath, duration / 3);
+            foreach (var stats in maybeStats)
+            {
+                if (stats.TotalFrames == 0)
+                {
+                    return 0;
+                }
+
+                return (double)stats.TotalInterlacedFrames / stats.TotalInterlacedFrames;
+            }
+        }
+        catch (Exception ex)
+        {
+            _logger.LogWarning(ex, "Failed to check interlaced ratio for media item {Id}", mediaItem.Id);
+        }
+
+        return Option<double>.None;
+    }
+
     private async Task<Either<BaseError, bool>> RefreshStatistics(
         string ffmpegPath,
         string ffprobePath,
@@ -200,8 +246,7 @@ public class LocalStatisticsProvider : ILocalStatisticsProvider
         FFprobe ffprobe = JsonConvert.DeserializeObject<FFprobe>(probe.StandardOutput);
         if (ffprobe is not null)
         {
-            const string PATTERN = @"\[SAR\s+([0-9]+:[0-9]+)\s+DAR\s+([0-9]+:[0-9]+)\]";
-            Match match = Regex.Match(probe.StandardError, PATTERN);
+            Match match = SarDarRegex().Match(probe.StandardError);
             if (match.Success)
             {
                 string sar = match.Groups[1].Value;
@@ -234,6 +279,55 @@ public class LocalStatisticsProvider : ILocalStatisticsProvider
         return BaseError.New("Unable to deserialize ffprobe output");
     }
 
+    private async Task<Option<IdetStatistics>> GetIdetOutput(string ffmpegPath, string filePath, TimeSpan seek)
+    {
+        string[] arguments =
+        [
+            "-hide_banner",
+            "-ss", $"{seek:c}",
+            "-i", filePath,
+            "-vf", "idet",
+            "-frames:v", "200",
+            "-an",
+            "-f", "null", "-"
+        ];
+
+        BufferedCommandResult idet = await Cli.Wrap(ffmpegPath)
+            .WithArguments(arguments)
+            .WithValidation(CommandResultValidation.None)
+            .ExecuteBufferedAsync(Encoding.UTF8);
+
+        if (idet.ExitCode != 0)
+        {
+            _logger.LogInformation(
+                "FFmpeg idet with arguments {Arguments} exited with code {ExitCode}",
+                arguments,
+                idet.ExitCode);
+
+            return Option<IdetStatistics>.None;
+        }
+
+        var stats = new IdetStatistics();
+
+        var singleMatch = SingleFrameRegex().Match(idet.StandardOutput);
+        if (singleMatch.Success)
+        {
+            stats.SingleTff = int.Parse(singleMatch.Groups[1].Value, NumberFormatInfo.InvariantInfo);
+            stats.SingleBff = int.Parse(singleMatch.Groups[2].Value, NumberFormatInfo.InvariantInfo);
+            stats.SingleProgressive = int.Parse(singleMatch.Groups[3].Value, NumberFormatInfo.InvariantInfo);
+        }
+
+        var multiMatch = MultiFrameRegex().Match(idet.StandardOutput);
+        if (multiMatch.Success)
+        {
+            stats.MultiTff = int.Parse(multiMatch.Groups[1].Value, NumberFormatInfo.InvariantInfo);
+            stats.MultiBff = int.Parse(multiMatch.Groups[2].Value, NumberFormatInfo.InvariantInfo);
+            stats.MultiProgressive = int.Parse(multiMatch.Groups[3].Value, NumberFormatInfo.InvariantInfo);
+        }
+
+        return stats;
+    }
+
     private async Task AnalyzeDuration(string ffmpegPath, string path, MediaVersion version)
     {
         try
@@ -366,6 +460,7 @@ public class LocalStatisticsProvider : ILocalStatisticsProvider
                         version.Width = videoStream.width;
                         version.Height = videoStream.height;
                         version.VideoScanKind = ScanKindFromFieldOrder(videoStream.field_order);
+                        version.InterlacedRatio = null;
                         version.RFrameRate = videoStream.r_frame_rate;
 
                         var stream = new MediaStream
@@ -600,4 +695,27 @@ public class LocalStatisticsProvider : ILocalStatisticsProvider
             null);
     }
     // ReSharper restore InconsistentNaming
+
+    [GeneratedRegex(@"\[SAR\s+([0-9]+:[0-9]+)\s+DAR\s+([0-9]+:[0-9]+)\]")]
+    private static partial Regex SarDarRegex();
+
+    [GeneratedRegex(@"Single frame detection: TFF: (\d+) BFF: (\d+) Progressive: (\d+)")]
+    private static partial Regex SingleFrameRegex();
+
+    [GeneratedRegex(@"Multi frame detection: TFF: (\d+) BFF: (\d+) Progressive: (\d+)")]
+    private static partial Regex MultiFrameRegex();
+
+    private class IdetStatistics
+    {
+        public int SingleTff { get; set; }
+        public int SingleBff { get; set; }
+        public int SingleProgressive { get; set; }
+        public int MultiTff { get; set; }
+        public int MultiBff { get; set; }
+        public int MultiProgressive { get; set; }
+
+        public int TotalInterlacedFrames => SingleTff + SingleBff + MultiTff + MultiBff;
+        public int TotalProgressiveFrames => SingleProgressive + MultiProgressive;
+        public int TotalFrames => TotalInterlacedFrames + TotalProgressiveFrames;
+    }
 }

ErsatzTV.Scanner.Tests/Core/FFmpeg/TranscodingTests.cs

@@ -283,6 +283,8 @@ public class TranscodingTests
             graphicsElementLoader,
             MemoryCache,
             Substitute.For<IMpegTsScriptService>(),
+            Substitute.For<ILocalStatisticsProvider>(),
+            Substitute.For<IMediaItemRepository>(),
             LoggerFactory.CreateLogger<FFmpegLibraryProcessService>());
 
         var songVideoGenerator = new SongVideoGenerator(tempFilePool, mockImageCache, service);
@@ -375,7 +377,7 @@ public class TranscodingTests
             ExecutableName("ffprobe"),
             true,
             channel,
-            videoVersion,
+            new MediaItemVideoVersion(song, videoVersion),
             new MediaItemAudioVersion(song, songVersion),
             videoPath,
             file,
@@ -695,7 +697,7 @@ public class TranscodingTests
             ExecutableName("ffprobe"),
             true,
             channel,
-            v,
+            new MediaItemVideoVersion(null, v),
             new MediaItemAudioVersion(null, v),
             file,
             file,
@@ -990,6 +992,8 @@ public class TranscodingTests
             graphicsElementLoader,
             MemoryCache,
             Substitute.For<IMpegTsScriptService>(),
+            Substitute.For<ILocalStatisticsProvider>(),
+            Substitute.For<IMediaItemRepository>(),
             LoggerFactory.CreateLogger<FFmpegLibraryProcessService>());
 
         return service;

ErsatzTV/Pages/Settings/FFmpegSettings.razor

@@ -68,6 +68,12 @@
                 </div>
                 <MudCheckBox @bind-Value="_ffmpegSettings.ExtractEmbeddedSubtitles" Disabled="@(_ffmpegSettings.UseEmbeddedSubtitles == false)" Dense="true"/>
             </MudStack>
+            <MudStack Row="true" Breakpoint="Breakpoint.SmAndDown" Class="form-field-stack gap-md-8 mb-5">
+                <div class="d-flex">
+                    <MudText>Probe For Interlaced Frames</MudText>
+                </div>
+                <MudCheckBox @bind-Value="_ffmpegSettings.ProbeForInterlacedFrames" Dense="true"/>
+            </MudStack>
             <MudStack Row="true" Breakpoint="Breakpoint.SmAndDown" Class="form-field-stack gap-md-8 mb-5">
                 <div class="d-flex">
                     <MudText>Save Troubleshooting Reports To Disk</MudText>