flowframes/Code/Media/FfmpegUtils.cs

using Flowframes.Data;
using Flowframes.Data.Streams;
using Flowframes.IO;
using Flowframes.MiscUtils;
using System;
using System.Collections.Generic;
using System.Drawing;
using System.IO;
using System.Linq;
using System.Threading.Tasks;
using static Flowframes.Media.GetVideoInfo;
using Stream = Flowframes.Data.Streams.Stream;

namespace Flowframes.Media
{
    class FfmpegUtils
    {
        private readonly static FfprobeMode showStreams = FfprobeMode.ShowStreams;
        private readonly static FfprobeMode showFormat = FfprobeMode.ShowFormat;

        public static async Task<int> GetStreamCount(string path)
        {
            Logger.Log($"GetStreamCount({path})", true);
            string output = await GetFfmpegInfoAsync(path, "Stream #0:");

            if (string.IsNullOrWhiteSpace(output.Trim()))
                return 0;

            return output.SplitIntoLines().Where(x => x.MatchesWildcard("*Stream #0:*: *: *")).Count();
        }

        public static async Task<List<Stream>> GetStreams(string path, bool progressBar, int streamCount, Fraction defaultFps, bool countFrames)
        {
            List<Stream> streamList = new List<Stream>();

            try
            {
                string output = await GetFfmpegInfoAsync(path, "Stream #0:");
                string[] streams = output.SplitIntoLines().Where(x => x.MatchesWildcard("*Stream #0:*: *: *")).ToArray();

                foreach (string streamStr in streams)
                {
                    try
                    {
                        int idx = streamStr.Split(':')[1].Split('[')[0].Split('(')[0].GetInt();
                        bool def = await GetFfprobeInfoAsync(path, showStreams, "DISPOSITION:default", idx) == "1";

                        if (progressBar)
                            Program.mainForm.SetProgress(FormatUtils.RatioInt(idx + 1, streamCount));

                        if (streamStr.Contains(": Video:"))
                        {
                            string lang = await GetFfprobeInfoAsync(path, showStreams, "TAG:language", idx);
                            string title = await GetFfprobeInfoAsync(path, showStreams, "TAG:title", idx);
                            string codec = await GetFfprobeInfoAsync(path, showStreams, "codec_name", idx);
                            string codecLong = await GetFfprobeInfoAsync(path, showStreams, "codec_long_name", idx);
                            string pixFmt = (await GetFfprobeInfoAsync(path, showStreams, "pix_fmt", idx)).ToUpper();
                            int kbits = (await GetFfprobeInfoAsync(path, showStreams, "bit_rate", idx)).GetInt() / 1024;
                            Size res = await GetMediaResolutionCached.GetSizeAsync(path);
                            Size sar = SizeFromString(await GetFfprobeInfoAsync(path, showStreams, "sample_aspect_ratio", idx));
                            Size dar = SizeFromString(await GetFfprobeInfoAsync(path, showStreams, "display_aspect_ratio", idx));
                            Fraction fps = path.IsConcatFile() ? defaultFps : await IoUtils.GetVideoFramerate(path);
                            int frameCount = countFrames ? await GetFrameCountCached.GetFrameCountAsync(path) : 0;
                            VideoStream vStream = new VideoStream(lang, title, codec, codecLong, pixFmt, kbits, res, sar, dar, fps, frameCount);
                            vStream.Index = idx;
                            vStream.IsDefault = def;
                            Logger.Log($"Added video stream: {vStream}", true);
                            streamList.Add(vStream);
                            continue;
                        }

                        if (streamStr.Contains(": Audio:"))
                        {
                            string lang = await GetFfprobeInfoAsync(path, showStreams, "TAG:language", idx);
                            string title = await GetFfprobeInfoAsync(path, showStreams, "TAG:title", idx);
                            string codec = await GetFfprobeInfoAsync(path, showStreams, "codec_name", idx);
                            string profile = await GetFfprobeInfoAsync(path, showStreams, "profile", idx);
                            if (codec.ToLower() == "dts" && profile != "unknown") codec = profile;
                            string codecLong = await GetFfprobeInfoAsync(path, showStreams, "codec_long_name", idx);
                            int kbits = (await GetFfprobeInfoAsync(path, showStreams, "bit_rate", idx)).GetInt() / 1024;
                            int sampleRate = (await GetFfprobeInfoAsync(path, showStreams, "sample_rate", idx)).GetInt();
                            int channels = (await GetFfprobeInfoAsync(path, showStreams, "channels", idx)).GetInt();
                            string layout = (await GetFfprobeInfoAsync(path, showStreams, "channel_layout", idx));
                            AudioStream aStream = new AudioStream(lang, title, codec, codecLong, kbits, sampleRate, channels, layout);
                            aStream.Index = idx;
                            aStream.IsDefault = def;
                            Logger.Log($"Added audio stream: {aStream}", true);
                            streamList.Add(aStream);
                            continue;
                        }

                        if (streamStr.Contains(": Subtitle:"))
                        {
                            string lang = await GetFfprobeInfoAsync(path, showStreams, "TAG:language", idx);
                            string title = await GetFfprobeInfoAsync(path, showStreams, "TAG:title", idx);
                            string codec = await GetFfprobeInfoAsync(path, showStreams, "codec_name", idx);
                            string codecLong = await GetFfprobeInfoAsync(path, showStreams, "codec_long_name", idx);
                            bool bitmap = await IsSubtitleBitmapBased(path, idx, codec);
                            SubtitleStream sStream = new SubtitleStream(lang, title, codec, codecLong, bitmap);
                            sStream.Index = idx;
                            sStream.IsDefault = def;
                            Logger.Log($"Added subtitle stream: {sStream}", true);
                            streamList.Add(sStream);
                            continue;
                        }

                        if (streamStr.Contains(": Data:"))
                        {
                            string codec = await GetFfprobeInfoAsync(path, showStreams, "codec_name", idx);
                            string codecLong = await GetFfprobeInfoAsync(path, showStreams, "codec_long_name", idx);
                            DataStream dStream = new DataStream(codec, codecLong);
                            dStream.Index = idx;
                            dStream.IsDefault = def;
                            Logger.Log($"Added data stream: {dStream}", true);
                            streamList.Add(dStream);
                            continue;
                        }

                        if (streamStr.Contains(": Attachment:"))
                        {
                            string codec = await GetFfprobeInfoAsync(path, showStreams, "codec_name", idx);
                            string codecLong = await GetFfprobeInfoAsync(path, showStreams, "codec_long_name", idx);
                            string filename = await GetFfprobeInfoAsync(path, showStreams, "TAG:filename", idx);
                            string mimeType = await GetFfprobeInfoAsync(path, showStreams, "TAG:mimetype", idx);
                            AttachmentStream aStream = new AttachmentStream(codec, codecLong, filename, mimeType);
                            aStream.Index = idx;
                            aStream.IsDefault = def;
                            Logger.Log($"Added attachment stream: {aStream}", true);
                            streamList.Add(aStream);
                            continue;
                        }

                        Logger.Log($"Unknown stream (not vid/aud/sub/dat/att): {streamStr}", true);
                        Stream stream = new Stream { Codec = "Unknown", CodecLong = "Unknown", Index = idx, IsDefault = def, Type = Stream.StreamType.Unknown };
                        streamList.Add(stream);
                    }
                    catch (Exception e)
                    {
                        Logger.Log($"Error scanning stream: {e.Message}\n{e.StackTrace}");
                    }
                }
            }
            catch (Exception e)
            {
                Logger.Log($"GetStreams Exception: {e.Message}\n{e.StackTrace}", true);
            }

            Logger.Log($"Video Streams: {string.Join(", ", streamList.Where(x => x.Type == Stream.StreamType.Video).Select(x => string.IsNullOrWhiteSpace(x.Title) ? "No Title" : x.Title))}", true);
            Logger.Log($"Audio Streams: {string.Join(", ", streamList.Where(x => x.Type == Stream.StreamType.Audio).Select(x => string.IsNullOrWhiteSpace(x.Title) ? "No Title" : x.Title))}", true);
            Logger.Log($"Subtitle Streams: {string.Join(", ", streamList.Where(x => x.Type == Stream.StreamType.Subtitle).Select(x => string.IsNullOrWhiteSpace(x.Title) ? "No Title" : x.Title))}", true);

            if (progressBar)
                Program.mainForm.SetProgress(0);

            return streamList;
        }

        public static async Task<bool> IsSubtitleBitmapBased(string path, int streamIndex, string codec = "")
        {
            if (codec == "ssa" || codec == "ass" || codec == "mov_text" || codec == "srt" || codec == "subrip" || codec == "text" || codec == "webvtt")
                return false;

            if (codec == "dvdsub" || codec == "dvd_subtitle" || codec == "pgssub" || codec == "hdmv_pgs_subtitle" || codec.StartsWith("dvb_"))
                return true;

            // If codec was not listed above, manually check if it's compatible by trying to encode it:
            //string ffmpegCheck = await GetFfmpegOutputAsync(path, $"-map 0:{streamIndex} -c:s srt -t 0 -f null -");
            //return ffmpegCheck.Contains($"encoding currently only possible from text to text or bitmap to bitmap");

            return false;
        }

        public enum Codec { H264, H265, H264Nvenc, H265Nvenc, Av1, Vp9, ProRes, AviRaw, Gif }

        public static Codec GetCodec(Interpolate.OutMode mode)
        {
            if (mode == Interpolate.OutMode.VidMp4 || mode == Interpolate.OutMode.VidMkv)
            {
                int mp4MkvEnc = Config.GetInt(Config.Key.mp4Enc);
                if (mp4MkvEnc == 0) return Codec.H264;
                if (mp4MkvEnc == 1) return Codec.H265;
                if (mp4MkvEnc == 2) return Codec.H264Nvenc;
                if (mp4MkvEnc == 3) return Codec.H265Nvenc;
                if (mp4MkvEnc == 4) return Codec.Av1;
            }

            if (mode == Interpolate.OutMode.VidWebm)
                return Codec.Vp9;

            if (mode == Interpolate.OutMode.VidProRes)
                return Codec.ProRes;

            if (mode == Interpolate.OutMode.VidAvi)
                return Codec.AviRaw;

            if (mode == Interpolate.OutMode.VidGif)
                return Codec.Gif;

            return Codec.H264;
        }

        public static string GetEnc(Codec codec)
        {
            switch (codec)
            {
                case Codec.H264: return "libx264";
                case Codec.H265: return "libx265";
                case Codec.H264Nvenc: return "h264_nvenc";
                case Codec.H265Nvenc: return "hevc_nvenc";
                case Codec.Av1: return "libsvtav1";
                case Codec.Vp9: return "libvpx-vp9";
                case Codec.ProRes: return "prores_ks";
                case Codec.AviRaw: return Config.Get(Config.Key.aviCodec);
                case Codec.Gif: return "gif";
            }

            return "libx264";
        }

        public static string[] GetEncArgs(Codec codec, Size res, float fps, bool realtime = false) // Array contains as many entries as there are encoding passes. If "realtime" is true, force single pass.
        {
            int keyint = 10;

            if (codec == Codec.H264)
            {
                string preset = Config.Get(Config.Key.ffEncPreset).ToLower().Remove(" ");
                string g = GetKeyIntArg(fps, keyint);
                return new string[] { $"-c:v {GetEnc(codec)} -crf {Config.GetInt(Config.Key.h264Crf)} -preset {preset} {g} -pix_fmt {GetPixFmt()}" };
            }

            if (codec == Codec.H265)
            {
                string preset = Config.Get(Config.Key.ffEncPreset).ToLower().Remove(" ");
                int crf = Config.GetInt(Config.Key.h265Crf);
                string g = GetKeyIntArg(fps, keyint);
                return new string[] { $"-c:v {GetEnc(codec)} {(crf > 0 ? $"-crf {crf}" : "-x265-params lossless=1")} -preset {preset} {g} -pix_fmt {GetPixFmt()}" };
            }

            if (codec == Codec.H264Nvenc)
            {
                int cq = (Config.GetInt(Config.Key.h264Crf) * 1.1f).RoundToInt();
                return new string[] { $"-c:v {GetEnc(codec)} -b:v 0 {(cq > 0 ? $"-cq {cq} -preset p7" : "-preset lossless")} -pix_fmt {GetPixFmt()}" };
            }

            if (codec == Codec.H265Nvenc)
            {
                int cq = (Config.GetInt(Config.Key.h265Crf) * 1.1f).RoundToInt();
                return new string[] { $"-c:v {GetEnc(codec)} -b:v 0 {(cq > 0 ? $"-cq {cq} -preset p7" : "-preset lossless")} -pix_fmt {GetPixFmt()}" };
            }

            if (codec == Codec.Av1)
            {
                int cq = Config.GetInt(Config.Key.av1Crf);
                string g = GetKeyIntArg(fps, keyint);
                return new string[] { $"-c:v {GetEnc(codec)} -b:v 0 -qp {cq} {GetSvtAv1Speed()} {g} -svtav1-params enable-overlays=0:enable-tf=0:scd=0 -pix_fmt {GetPixFmt()}" };
            }

            if (codec == Codec.Vp9)
            {
                int crf = Config.GetInt(Config.Key.vp9Crf);
                string qualityStr = (crf > 0) ? $"-crf {crf}" : "-lossless 1";
                string g = GetKeyIntArg(fps, keyint);
                string t = GetTilingArgs(res, "-tile-columns ", "-tile-rows ");

                if (realtime) // Force 1-pass
                {
                    return new string[] { $"-c:v {GetEnc(codec)} -b:v 0 {qualityStr} {GetVp9Speed()} {t} -row-mt 1 {g} -pix_fmt {GetPixFmt()}" };
                }
                else
                {
                    return new string[] { 
                        $"-c:v {GetEnc(codec)} -b:v 0 {qualityStr} {GetVp9Speed()} {t} -row-mt 1 {g} -pass 1 -pix_fmt {GetPixFmt()} -an", 
                        $"-c:v {GetEnc(codec)} -b:v 0 {qualityStr} {GetVp9Speed()} {t} -row-mt 1 {g} -pass 2 -pix_fmt {GetPixFmt()}"
                    };
                }
            }

            if (codec == Codec.ProRes)
            {
                return new string[] { $"-c:v {GetEnc(codec)} -profile:v {Config.GetInt(Config.Key.proResProfile)} -pix_fmt {GetPixFmt()}" };
            }

            if (codec == Codec.AviRaw)
            {
                return new string[] { $"-c:v {GetEnc(codec)} -pix_fmt {Config.Get(Config.Key.aviColors)}" };
            }

            if (codec == Codec.Gif)
            {
                return new string[] { $"-c:v {GetEnc(codec)} -gifflags -offsetting" };
            }

            return new string[0];
        }

        public static string GetTilingArgs(Size resolution, string colArg, string rowArg)
        {
            int cols = 0;
            if (resolution.Width >= 1920) cols = 1;
            if (resolution.Width >= 3840) cols = 2;
            if (resolution.Width >= 7680) cols = 3;

            int rows = 0;
            if (resolution.Height >= 1600) rows = 1;
            if (resolution.Height >= 3200) rows = 2;
            if (resolution.Height >= 6400) rows = 3;

            Logger.Log($"GetTilingArgs: Video resolution is {resolution.Width}x{resolution.Height} - Using 2^{cols} columns, 2^{rows} rows (=> {Math.Pow(2, cols)}x{Math.Pow(2, rows)} = {Math.Pow(2, cols) * Math.Pow(2, rows)} Tiles)", true);

            return $"{(cols > 0 ? colArg+cols : "")} {(rows > 0 ? rowArg + rows : "")}";
        }

        public static string GetKeyIntArg(float fps, int intervalSeconds, string arg = "-g ")
        {
            int keyInt = (fps * intervalSeconds).RoundToInt().Clamp(20, 300);
            return $"{arg}{keyInt}";
        }

        static string GetVp9Speed()
        {
            string preset = Config.Get(Config.Key.ffEncPreset).ToLower().Remove(" ");
            string arg = "";

            if (preset == "veryslow") arg = "0";
            if (preset == "slower") arg = "1";
            if (preset == "slow") arg = "2";
            if (preset == "medium") arg = "3";
            if (preset == "fast") arg = "4";
            if (preset == "faster") arg = "5";
            if (preset == "veryfast") arg = "4 -deadline realtime";

            return $"-cpu-used {arg}";
        }

        static string GetSvtAv1Speed()
        {
            string preset = Config.Get(Config.Key.ffEncPreset).ToLower().Remove(" ");
            string arg = "8";

            if (preset == "veryslow") arg = "3";
            if (preset == "slower") arg = "4";
            if (preset == "slow") arg = "5";
            if (preset == "medium") arg = "6";
            if (preset == "fast") arg = "7";
            if (preset == "faster") arg = "8";
            if (preset == "veryfast") arg = "9";

            return $"-preset {arg}";
        }

        static string GetPixFmt()
        {
            switch (Config.GetInt(Config.Key.pixFmt))
            {
                case 0: return "yuv420p";
                case 1: return "yuv444p";
                case 2: return "yuv420p10le";
                case 3: return "yuv444p10le";
            }

            return "yuv420p";
        }

        public static bool ContainerSupportsAllAudioFormats(Interpolate.OutMode outMode, List<string> codecs)
        {
            if (codecs.Count < 1)
                Logger.Log($"Warning: ContainerSupportsAllAudioFormats() was called, but codec list has {codecs.Count} entries.", true, false, "ffmpeg");

            foreach (string format in codecs)
            {
                if (!ContainerSupportsAudioFormat(outMode, format))
                    return false;
            }

            return true;
        }

        public static bool ContainerSupportsAudioFormat(Interpolate.OutMode outMode, string format)
        {
            bool supported = false;
            string alias = GetAudioExt(format);

            string[] formatsMp4 = new string[] { "m4a", "mp3", "ac3", "dts" };
            string[] formatsMkv = new string[] { "m4a", "mp3", "ac3", "dts", "ogg", "mp2", "wav", "wma" };
            string[] formatsWebm = new string[] { "ogg" };
            string[] formatsProres = new string[] { "m4a", "ac3", "dts", "wav" };
            string[] formatsAvi = new string[] { "m4a", "ac3", "dts" };

            switch (outMode)
            {
                case Interpolate.OutMode.VidMp4: supported = formatsMp4.Contains(alias); break;
                case Interpolate.OutMode.VidMkv: supported = formatsMkv.Contains(alias); break;
                case Interpolate.OutMode.VidWebm: supported = formatsWebm.Contains(alias); break;
                case Interpolate.OutMode.VidProRes: supported = formatsProres.Contains(alias); break;
                case Interpolate.OutMode.VidAvi: supported = formatsAvi.Contains(alias); break;
            }

            Logger.Log($"Checking if {outMode} supports audio format '{format}' ({alias}): {supported}", true, false, "ffmpeg");
            return supported;
        }

        public static string GetExt(Interpolate.OutMode outMode, bool dot = true)
        {
            string ext = dot ? "." : "";

            switch (outMode)
            {
                case Interpolate.OutMode.VidMp4: ext += "mp4"; break;
                case Interpolate.OutMode.VidMkv: ext += "mkv"; break;
                case Interpolate.OutMode.VidWebm: ext += "webm"; break;
                case Interpolate.OutMode.VidProRes: ext += "mov"; break;
                case Interpolate.OutMode.VidAvi: ext += "avi"; break;
                case Interpolate.OutMode.VidGif: ext += "gif"; break;
            }

            return ext;
        }

        public static string GetAudioExt(string codec)
        {
            if (codec.StartsWith("pcm_"))
                return "wav";

            switch (codec)
            {
                case "vorbis": return "ogg";
                case "opus": return "ogg";
                case "mp2": return "mp2";
                case "mp3": return "mp3";
                case "aac": return "m4a";
                case "ac3": return "ac3";
                case "eac3": return "ac3";
                case "dts": return "dts";
                case "alac": return "wav";
                case "flac": return "wav";
                case "wmav1": return "wma";
                case "wmav2": return "wma";
            }

            return "unsupported";
        }

        public static async Task<string> GetAudioFallbackArgs(string videoPath, Interpolate.OutMode outMode, float itsScale)
        {
            bool opusMp4 = Config.GetBool(Config.Key.allowOpusInMp4);
            int opusBr = Config.GetInt(Config.Key.opusBitrate, 128);
            int aacBr = Config.GetInt(Config.Key.aacBitrate, 160);
            int ac = (await GetVideoInfo.GetFfprobeInfoAsync(videoPath, GetVideoInfo.FfprobeMode.ShowStreams, "channels", 0)).GetInt();
            string af = GetAudioFilters(itsScale);

            if (outMode == Interpolate.OutMode.VidMkv || outMode == Interpolate.OutMode.VidWebm || (outMode == Interpolate.OutMode.VidMp4 && opusMp4))
                return $"-c:a libopus -b:a {(ac > 4 ? $"{opusBr * 2}" : $"{opusBr}")}k -ac {(ac > 0 ? $"{ac}" : "2")} {af}"; // Double bitrate if 5ch or more, ignore ac if <= 0
            else
                return $"-c:a aac -b:a {(ac > 4 ? $"{aacBr * 2}" : $"{aacBr}")}k -aac_coder twoloop -ac {(ac > 0 ? $"{ac}" : "2")} {af}";
        }

        private static string GetAudioFilters(float itsScale)
        {
            if (itsScale == 0 || itsScale == 1)
                return "";

            if (itsScale > 4)
                return $"-af atempo=0.5,atempo=0.5,atempo={((1f / itsScale) * 4).ToStringDot()}";
            else if (itsScale > 2)
                return $"-af atempo=0.5,atempo={((1f / itsScale) * 2).ToStringDot()}";
            else
                return $"-af atempo={(1f / itsScale).ToStringDot()}";
        }

        public static string GetSubCodecForContainer(string containerExt)
        {
            containerExt = containerExt.Remove(".");

            if (containerExt == "mp4" || containerExt == "mov") return "mov_text";
            if (containerExt == "webm") return "webvtt";

            return "copy";    // Default: Copy subs
        }

        public static bool ContainerSupportsSubs(string containerExt, bool showWarningIfNotSupported = true)
        {
            containerExt = containerExt.Remove(".");
            bool supported = (containerExt == "mp4" || containerExt == "mkv" || containerExt == "webm" || containerExt == "mov");
            Logger.Log($"Subtitles {(supported ? "are supported" : "not supported")} by {containerExt.ToUpper()}", true);

            if (showWarningIfNotSupported && Config.GetBool(Config.Key.keepSubs) && !supported)
                Logger.Log($"Warning: {containerExt.ToUpper()} exports do not include subtitles.");

            return supported;
        }

        public static int CreateConcatFile(string inputFilesDir, string outputPath, List<string> validExtensions = null)
        {
            if (IoUtils.GetAmountOfFiles(inputFilesDir, false) < 1)
                return 0;

            Directory.CreateDirectory(outputPath.GetParentDir());

            if (validExtensions == null)
                validExtensions = new List<string>();

            validExtensions = validExtensions.Select(x => x.Remove(".").ToLower()).ToList(); // Ignore "." in extensions
            string concatFileContent = "";
            string[] files = IoUtils.GetFilesSorted(inputFilesDir);
            int fileCount = 0;

            foreach (string file in files.Where(x => validExtensions.Contains(Path.GetExtension(x).Replace(".", "").ToLower())))
            {
                fileCount++;
                concatFileContent += $"file '{file.Replace(@"\", "/")}'\n";
            }

            File.WriteAllText(outputPath, concatFileContent);
            return fileCount;
        }

        public static Size SizeFromString(string str, char delimiter = ':')
        {
            try
            {
                string[] nums = str.Remove(" ").Trim().Split(delimiter);
                return new Size(nums[0].GetInt(), nums[1].GetInt());
            }
            catch
            {
                return new Size();
            }
        }
    }
}