I've made my own setting presets for the Mpeg4 AVC (x264) encoder. To use them, save each file as text files named "Animation 14mb.json" and "Live Footage 14mb.json" respectively. Copy these into "C:\Users\[your user name]\AppData\Roaming\avidemux\pluginSettings\x264\3".
In Avidemux, select Mpeg4 AVC (x264) as your encoder and click Configure. At the top you can select your Configuration, choose Live Footage or Animation depending on your content. Click OK.
Then click Filters and find the resolution scaler (probably swsResize if you've got Avidemux 2.7.0). I like to go around 800x450 so the video is a bit smoother, but 845x480 for a native 16:9 aspect video also works fine. 640x360 if you really want to save some space.
It's already set to use File Size to determine bitrate so it shouldn't go over 14mb however this can usually be put down way lower without noticeable artifacts. I've been able to compress some live footage content down to just 7mb and have it look identical to a 14mb version (to me at least).
Live Footage 14mb.json{
"useAdvancedConfiguration" : true,
"general" : {
"params" : "2PASS=13",
"threads" : 0,
"preset" : "ultrafast",
"tuning" : "none",
"profile" : "baseline",
"fast_decode" : false,
"zero_latency" : false,
"fast_first_pass" : true,
"blueray_compatibility" : false,
"fake_interlaced" : false
},
"level" : -1,
"vui" : {
"sar_height" : 1,
"sar_width" : 1
},
"MaxRefFrames" : 3,
"MinIdr" : 25,
"MaxIdr" : 250,
"i_scenecut_threshold" : 38,
"intra_refresh" : false,
"MaxBFrame" : 5,
"i_bframe_adaptive" : 2,
"i_bframe_bias" : 0,
"i_bframe_pyramid" : 2,
"b_deblocking_filter" : true,
"i_deblocking_filter_alphac0" : 0,
"i_deblocking_filter_beta" : 0,
"cabac" : true,
"interlaced" : false,
"constrained_intra" : false,
"tff" : true,
"fake_interlaced" : false,
"analyze" : {
"b_8x8" : true,
"b_i4x4" : true,
"b_i8x8" : true,
"b_p8x8" : false,
"b_p16x16" : true,
"b_b16x16" : true,
"weighted_pred" : 2,
"weighted_bipred" : true,
"direct_mv_pred" : 3,
"chroma_offset" : 0,
"me_method" : 2,
"me_range" : 24,
"mv_range" : -1,
"mv_range_thread" : -1,
"subpel_refine" : 7,
"chroma_me" : true,
"mixed_references" : true,
"trellis" : 2,
"psy_rd" : 1,
"psy_trellis" : 0.1,
"fast_pskip" : false,
"dct_decimate" : true,
"noise_reduction" : 0,
"psy" : true,
"intra_luma" : 11,
"inter_luma" : 21
},
"ratecontrol" : {
"rc_method" : 0,
"qp_constant" : 0,
"qp_min" : 10,
"qp_max" : 51,
"qp_step" : 4,
"bitrate" : 0,
"rate_tolerance" : 1,
"vbv_max_bitrate" : 0,
"vbv_buffer_size" : 0,
"vbv_buffer_init" : 1,
"ip_factor" : 1.4,
"pb_factor" : 1.3,
"aq_mode" : 1,
"aq_strength" : 1,
"mb_tree" : true,
"lookahead" : 50
}
}
Animation 14mb.json{
"useAdvancedConfiguration" : true,
"general" : {
"params" : "2PASS=13",
"threads" : 0,
"preset" : "ultrafast",
"tuning" : "none",
"profile" : "baseline",
"fast_decode" : false,
"zero_latency" : false,
"fast_first_pass" : true,
"blueray_compatibility" : false,
"fake_interlaced" : false
},
"level" : -1,
"vui" : {
"sar_height" : 1,
"sar_width" : 1
},
"MaxRefFrames" : 16,
"MinIdr" : 25,
"MaxIdr" : 250,
"i_scenecut_threshold" : 38,
"intra_refresh" : false,
"MaxBFrame" : 8,
"i_bframe_adaptive" : 2,
"i_bframe_bias" : 0,
"i_bframe_pyramid" : 2,
"b_deblocking_filter" : true,
"i_deblocking_filter_alphac0" : 1,
"i_deblocking_filter_beta" : 2,
"cabac" : true,
"interlaced" : false,
"constrained_intra" : false,
"tff" : true,
"fake_interlaced" : false,
"analyze" : {
"b_8x8" : true,
"b_i4x4" : true,
"b_i8x8" : true,
"b_p8x8" : false,
"b_p16x16" : true,
"b_b16x16" : true,
"weighted_pred" : 2,
"weighted_bipred" : true,
"direct_mv_pred" : 3,
"chroma_offset" : 0,
"me_method" : 2,
"me_range" : 24,
"mv_range" : -1,
"mv_range_thread" : -1,
"subpel_refine" : 7,
"chroma_me" : true,
"mixed_references" : true,
"trellis" : 2,
"psy_rd" : 0.4,
"psy_trellis" : 0,
"fast_pskip" : false,
"dct_decimate" : true,
"noise_reduction" : 0,
"psy" : true,
"intra_luma" : 11,
"inter_luma" : 21
},
"ratecontrol" : {
"rc_method" : 0,
"qp_constant" : 0,
"qp_min" : 10,
"qp_max" : 51,
"qp_step" : 4,
"bitrate" : 0,
"rate_tolerance" : 1,
"vbv_max_bitrate" : 0,
"vbv_buffer_size" : 0,
"vbv_buffer_init" : 1,
"ip_factor" : 1.4,
"pb_factor" : 1.3,
"aq_mode" : 1,
"aq_strength" : 0.6,
"mb_tree" : true,
"lookahead" : 50
}
}