From 454cbc96b7c81109b1d7fd24df1da99ba30f5207 Mon Sep 17 00:00:00 2001 From: John Koleszar Date: Tue, 19 Apr 2011 14:05:27 -0400 Subject: [PATCH] Limit size of initial keyframe in one-pass. Rather than using a default size of 1/2 or 3/2 seconds for the first frame, use a fraction of the initial buffer level to give the application some control. This will likely undergo further refinement as size limits on key frames are currently under discussion on codec-devel@, but this gives much better behavior for small buffer sizes as a starting point. Change-Id: Ieba55b86517b81e51e6f0a9fe27aabba295acab0 --- vp8/encoder/onyx_if.c | 23 ++++++++++++----------- 1 file changed, 12 insertions(+), 11 deletions(-) diff --git a/vp8/encoder/onyx_if.c b/vp8/encoder/onyx_if.c index cbaab5f..4208f1f 100644 --- a/vp8/encoder/onyx_if.c +++ b/vp8/encoder/onyx_if.c @@ -1459,10 +1459,6 @@ static void init_config(VP8_PTR ptr, VP8_CONFIG *oxcf) cpi->avg_frame_qindex = cpi->oxcf.worst_allowed_q; // Initialise the starting buffer levels - cpi->oxcf.starting_buffer_level = - rescale(cpi->oxcf.starting_buffer_level, - cpi->oxcf.target_bandwidth, 1000); - cpi->buffer_level = cpi->oxcf.starting_buffer_level; cpi->bits_off_target = cpi->oxcf.starting_buffer_level; @@ -1635,6 +1631,10 @@ void vp8_change_config(VP8_PTR ptr, VP8_CONFIG *oxcf) // Convert target bandwidth from Kbit/s to Bit/s cpi->oxcf.target_bandwidth *= 1000; + cpi->oxcf.starting_buffer_level = + rescale(cpi->oxcf.starting_buffer_level, + cpi->oxcf.target_bandwidth, 1000); + // Set or reset optimal and maximum buffer levels. if (cpi->oxcf.optimal_buffer_level == 0) cpi->oxcf.optimal_buffer_level = cpi->oxcf.target_bandwidth / 8; @@ -2661,16 +2661,17 @@ static int pick_frame_size(VP8_COMP *cpi) if (cpi->pass == 2) vp8_calc_auto_iframe_target_size(cpi); - // 1 Pass there is no information on which to base size so use bandwidth per second * fixed fraction else #endif - cpi->this_frame_target = cpi->oxcf.target_bandwidth / 2; - - // in error resilient mode the first frame is bigger since it likely contains - // all the static background - if (cpi->oxcf.error_resilient_mode == 1 || (cpi->compressor_speed == 2)) { - cpi->this_frame_target *= 3; // 5; + /* 1 Pass there is no information on which to base size so use + * bandwidth per second * fraction of the initial buffer + * level + */ + cpi->this_frame_target = cpi->oxcf.starting_buffer_level / 2; + + if(cpi->this_frame_target > cpi->oxcf.target_bandwidth * 3 / 2) + cpi->this_frame_target = cpi->oxcf.target_bandwidth * 3 / 2; } // Key frame from VFW/auto-keyframe/first frame -- 2.7.4