From 012e4a3e63f8b0997d5f070b37ac93d257f894e7 Mon Sep 17 00:00:00 2001 From: JMCC Date: Sat, 11 May 2019 17:19:20 +0200 Subject: Fix transcode bitrate control --- .../MediaEncoding/EncodingHelper.cs | 49 ++++++++++++++++------ 1 file changed, 36 insertions(+), 13 deletions(-) (limited to 'MediaBrowser.Controller/MediaEncoding/EncodingHelper.cs') diff --git a/MediaBrowser.Controller/MediaEncoding/EncodingHelper.cs b/MediaBrowser.Controller/MediaEncoding/EncodingHelper.cs index e378c2b89..849cf7083 100644 --- a/MediaBrowser.Controller/MediaEncoding/EncodingHelper.cs +++ b/MediaBrowser.Controller/MediaEncoding/EncodingHelper.cs @@ -1083,27 +1083,50 @@ namespace MediaBrowser.Controller.MediaEncoding { var bitrate = request.VideoBitRate; - // If specific values were requested, then force the caller to supply a bitrate as well - if (request.Height.HasValue && request.Width.HasValue) - { - return bitrate; - } - if (videoStream != null) { - if (bitrate.HasValue) - { - var inputVideoCodec = videoStream.Codec; - bitrate = ScaleBitrate(bitrate.Value, inputVideoCodec, outputVideoCodec); + var isUpscaling = request.Height.HasValue && videoStream.Height.HasValue && + request.Height.Value > videoStream.Height.Value && request.Width.HasValue && videoStream.Width.HasValue && + request.Width.Value > videoStream.Width.Value; - // If a max bitrate was requested, don't let the scaled bitrate exceed it - if (request.VideoBitRate.HasValue) + // Don't allow bitrate increases unless upscaling + if (!isUpscaling) + { + if (bitrate.HasValue && videoStream.BitRate.HasValue) { - bitrate = Math.Min(bitrate.Value, request.VideoBitRate.Value); + bitrate = GetMinBitrate(videoStream.BitRate.Value, bitrate.Value); } } } + if (bitrate.HasValue) + { + var inputVideoCodec = videoStream.Codec; + bitrate = ScaleBitrate(bitrate.Value, inputVideoCodec, outputVideoCodec); + + // If a max bitrate was requested, don't let the scaled bitrate exceed it + if (request.VideoBitRate.HasValue) + { + bitrate = Math.Min(bitrate.Value, request.VideoBitRate.Value); + } + } + + return bitrate; + } + + private int GetMinBitrate(int sourceBitrate, int requestedBitrate) + { + if (sourceBitrate <= 2000000) + { + sourceBitrate = Convert.ToInt32(sourceBitrate * 2.5); + } + else if (sourceBitrate <= 3000000) + { + sourceBitrate = Convert.ToInt32(sourceBitrate * 2); + } + + var bitrate = Math.Min(sourceBitrate, requestedBitrate); + return bitrate; } -- cgit v1.2.3 From 65fa61a6369bef8c7aa7cc2b9e6be383a2de3cb6 Mon Sep 17 00:00:00 2001 From: dkanada Date: Thu, 20 Jun 2019 16:44:27 -0700 Subject: add comment explaining GetMinBitrate --- MediaBrowser.Controller/MediaEncoding/EncodingHelper.cs | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'MediaBrowser.Controller/MediaEncoding/EncodingHelper.cs') diff --git a/MediaBrowser.Controller/MediaEncoding/EncodingHelper.cs b/MediaBrowser.Controller/MediaEncoding/EncodingHelper.cs index 849cf7083..2984efec3 100644 --- a/MediaBrowser.Controller/MediaEncoding/EncodingHelper.cs +++ b/MediaBrowser.Controller/MediaEncoding/EncodingHelper.cs @@ -1086,7 +1086,7 @@ namespace MediaBrowser.Controller.MediaEncoding if (videoStream != null) { var isUpscaling = request.Height.HasValue && videoStream.Height.HasValue && - request.Height.Value > videoStream.Height.Value && request.Width.HasValue && videoStream.Width.HasValue && + request.Height.Value > videoStream.Height.Value && request.Width.HasValue && videoStream.Width.HasValue && request.Width.Value > videoStream.Width.Value; // Don't allow bitrate increases unless upscaling @@ -1116,6 +1116,7 @@ namespace MediaBrowser.Controller.MediaEncoding private int GetMinBitrate(int sourceBitrate, int requestedBitrate) { + // these values were chosen from testing to improve low bitrate streams if (sourceBitrate <= 2000000) { sourceBitrate = Convert.ToInt32(sourceBitrate * 2.5); -- cgit v1.2.3