From 4e90e07993ae8e720a936707f23f82080eced8c9 Mon Sep 17 00:00:00 2001
From: Jonas Smedegaard <dr@jones.dk>
Date: Thu, 6 Apr 2017 16:15:04 +0200
Subject: Compute buffer sizes from bitrate.

---
 bin/stream.sh | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/bin/stream.sh b/bin/stream.sh
index 01ef12d..7b8a635 100755
--- a/bin/stream.sh
+++ b/bin/stream.sh
@@ -12,6 +12,7 @@ fi
 PORT=${2:-5004}
 
 SIZE=640x360
+BITRATE=500000
 
 MOVIE=../src/omni/show0/earth.mp4
 LOGO=../../content/icon_small.png
@@ -19,15 +20,13 @@ LOGO=../../content/icon_small.png
 # based on http://video.stackexchange.com/a/16933
 # + codec options from http://www.webmproject.org/docs/encoder-parameters/
 #   example "Real-time CBR Encoding and Streaming"
-#   (bufsize = 6000 * 500k / 1000)
-#   (rc_init_occupancy = 4000 * 500k / 1000)
 # + Drop frames, aggressively treat as static, and use fastest cpu
 ffmpeg -threads auto -re \
  -f lavfi -i "movie=filename=$MOVIE:loop=0, setpts=N/(FRAME_RATE*TB), scale=$SIZE" \
  -i "$LOGO" -filter_complex 'overlay=main_w-overlay_w-20:main_h-overlay_h-20' \
  -codec:v vp8 -quality realtime -deadline realtime -cpu-used 15 \
- -b:v 500k -minrate 500k -maxrate 500k \
- -undershoot-pct 95 -bufsize 3M -rc_init_occupancy 2M \
+ -b:v "$BITRATE" -minrate "$BITRATE" -maxrate "$BITRATE" \
+ -undershoot-pct 95 -bufsize $((6000*BITRATE/1000)) -rc_init_occupancy $((4000*BITRATE/1000)) \
  -max-intra-rate 0 \
  -qmin 4 -qmax 56 \
  -static-thresh 500 -skip_threshold 50 \
-- 
cgit v1.2.3