From: Steinar H. Gunderson <sgunderson@bigfoot.com>
Date: Tue, 24 Apr 2018 20:47:35 +0000 (+0200)
Subject: Make the FFmpegCapture disconnected frames proper black.
X-Git-Tag: 1.7.2~16
X-Git-Url: https://git.sesse.net/?p=nageru;a=commitdiff_plain;h=83157f6ffc2287cd861e938f85255cc0ba3506a1;hp=4c144e82c20912463cf7268723e564fa6eb8f1c0

Make the FFmpegCapture disconnected frames proper black.

Less disturbing, more consistent between BGRA and Y'CbCr, and the
all-zero Y'CbCr frame causes out-of-gamut (negative) RGB values that
ended up confusing white balance adjustment a lot.
---

diff --git a/ffmpeg_capture.cpp b/ffmpeg_capture.cpp
index b7db50c..235393a 100644
--- a/ffmpeg_capture.cpp
+++ b/ffmpeg_capture.cpp
@@ -327,6 +327,7 @@ void FFmpegCapture::send_disconnected_frame()
 		if (pixel_format == bmusb::PixelFormat_8BitBGRA) {
 			video_format.stride = width * 4;
 			video_frame.len = width * height * 4;
+			memset(video_frame.data, 0, video_frame.len);
 		} else {
 			video_format.stride = width;
 			current_frame_ycbcr_format.luma_coefficients = YCBCR_REC_709;
@@ -339,8 +340,9 @@ void FFmpegCapture::send_disconnected_frame()
 			current_frame_ycbcr_format.cr_x_position = 0.0f;
 			current_frame_ycbcr_format.cr_y_position = 0.0f;
 			video_frame.len = width * height * 2;
+			memset(video_frame.data, 0, width * height);
+			memset(video_frame.data + width * height, 128, width * height);  // Valid for both NV12 and planar.
 		}
-		memset(video_frame.data, 0, video_frame.len);
 
 		frame_callback(-1, AVRational{1, TIMEBASE}, -1, AVRational{1, TIMEBASE}, timecode++,
 			video_frame, /*video_offset=*/0, video_format,