hi roozhou.
is there any chance you might also make it capable of changing the SPS to lower Refs ?
care of DS way back in 24th December 2007,
http://forum.doom9.org/archive/index.php/t-133070.html
posted some Annex B data
"@0 SPS: profile_idc 01001101 ( 77)
@8 SPS: constrained_set0_flag 0 ( 0)
@9 SPS: constrained_set1_flag 1 ( 1)
@10 SPS: constrained_set2_flag 0 ( 0)
@11 SPS: constrained_set3_flag 0 ( 0)
@12 SPS: reserved_zero_4bits 0000 ( 0)
@16 SPS: level_idc 00101000 ( 40)
@24 SPS: seq_parameter_set_id 1 ( 0)
@25 SPS: log2_max_frame_num_minus4 0001001 ( 8)
@32 SPS: pic_order_cnt_type 1 ( 0)
@33 SPS: log2_max_pic_order_cnt_lsb_minus4 00110 ( 5)
@38 SPS: num_ref_frames 011 ( 2)
@41 SPS: gaps_in_frame_num_value_allowed_flag 0 ( 0)
@42 SPS: pic_width_in_mbs_minus1 0000001111000 (119)
@55 SPS: pic_height_in_map_units_minus1 00000100010 ( 33)
@66 SPS: frame_mbs_only_flag 0 ( 0)
@67 SPS: mb_adaptive_frame_field_flag 0 ( 0)
@68 SPS: direct_8x8_inference_flag 1 ( 1)
@69 SPS: frame_cropping_flag 0 ( 0)
@70 SPS: vui_parameters_present_flag 1 ( 1)"
im hoping "@38 SPS: num_ref_frames 011 ( 2)" is the ref values and its possible to change them to lower values in the bitstream copy without a full re-encode (or to much loss of quality playback if any ) through your ffmpeg extensions/patches if you can find a way to add that option sometime ? please.
it would be good for quick fixing streaming to the xbox360 and its limited ref 3 abilitys to play 1080AVC.Mp4 smoothly and perhaps other non (ref16) spec playback devices too.