Proxies: FFmpeg proxy builder wasn't taking image quality into account at all

which made it using default quality settings which are really bad for camera
tracking (and perhaps for CSE too).

haven't found Jpeg quality setting for FFmpeg which will behave in the same way
as quality setting for image sequence, but seems that mapping image quality
from 1..100 UI range to 31..1 range of qmin/qmax gives expected result.

1 files changed, 8 insertions, 1 deletions

diff --git a/source/blender/imbuf/intern/indexer.c b/source/blender/imbuf/intern/indexer.c
index e1481d2a08f..eb1bfc80383 100644
--- a/source/blender/imbuf/intern/indexer.c
+++ b/source/blender/imbuf/intern/indexer.c
@@ -459,12 +459,13 @@ static int round_up(int x, int mod)
 static struct proxy_output_ctx * alloc_proxy_output_ffmpeg(
 	struct anim * anim,
 	AVStream * st, int proxy_size, int width, int height,
-	int UNUSED(quality))
+	int quality)
 {
 	struct proxy_output_ctx * rv = MEM_callocN(
 		sizeof(struct proxy_output_ctx), "alloc_proxy_output");
 	
 	char fname[FILE_MAX];
+	int ffmpeg_quality;
 
 	// JPEG requires this
 	width = round_up(width, 8);
@@ -514,6 +515,12 @@ static struct proxy_output_ctx * alloc_proxy_output_ffmpeg(
 	rv->c->time_base.num = 1;
 	rv->st->time_base = rv->c->time_base;
 
+	/* there's no  way to set JPEG quality in the same way as in AVI JPEG and image sequence,
+	 * but this seems to be giving expected quality result */
+	ffmpeg_quality = 31 * (1.0f - (float)quality / 100.0f);
+	av_set_int(rv->c, "qmin", ffmpeg_quality);
+	av_set_int(rv->c, "qmax", ffmpeg_quality);
+
 	if (rv->of->flags & AVFMT_GLOBALHEADER) {
 		rv->c->flags |= CODEC_FLAG_GLOBAL_HEADER;
 	}