Conversion problem - Laggy (choppy) video

[yaang]

Basically i'm just trying to reduce the size of a h.264 720p video.

I'm using Megui and constant quality profile set to 21.

Problem is the output video comes out laggy, i don't think it's because of my hardware because i can play the original file smoothly. Weird thing is i always do a test run first to see if a set-up everything correctly by encoding the first 30 seconds at first and the motion was smooth. But when i finished encoding the whole thing it was laggy. I don't know how to describe it exactly, original of the video has 23.976fps and the encoded one seems to be running with 20fps but when i check it is 23.976. Motion isn't smooth it happens in tiny tiny jumps. I hope you understand what i'm talking about

Heres the info of the original file :

Video
ID : 1
Format : AVC
Format/Info : Advanced Video Codec
Format profile : High@L4.1
Format settings, CABAC : Yes
Format settings, ReFrames : 10 frames
Muxing mode : Container profile=Unknown@4.1
Codec ID : V_MPEG4/ISO/AVC
Duration : 2h 33mn
Bit rate : 5 762 Kbps
Nominal bit rate : 5 908 Kbps
Width : 1 280 pixels
Height : 534 pixels
Display aspect ratio : 2.35:1
Frame rate : 23.976 fps
Resolution : 24 bits
Colorimetry : 4:2:0
Scan type : Progressive
Bits/(Pixel*Frame) : 0.352
Stream size : 6.17 GiB (78%)
Writing library : x264 core 68 r1179M 96e2229
Encoding settings : cabac=1 / ref=10 / deblock=1:-3:-3 / analyse=0x3:0x133 / me=esa / subme=9 / psy_rd=1.0:0.1 / mixed_ref=1 / me_range=48 / chroma_me=1 / trellis=2 / 8x8dct=1 / cqm=0 / deadzone=21,11 / chroma_qp_offset=-3 / threads=12 / nr=0 / decimate=1 / mbaff=0 / bframes=6 / b_pyramid=1 / b_adapt=2 / b_bias=0 / direct=1 / wpredb=1 / keyint=250 / keyint_min=25 / scenecut=40 / rc=2pass / bitrate=5908 / ratetol=1.0 / qcomp=0.60 / qpmin=10 / qpmax=51 / qpstep=4 / cplxblur=20.0 / qblur=0.5 / vbv_maxrate=50000 / vbv_bufsize=50000 / ip_ratio=1.40 / pb_ratio=1.30 / aq=1:0.80
Language : English

Here's my re-encoded verison:

Video
ID : 1
Format : AVC
Format/Info : Advanced Video Codec
Format profile : High@L3.1
Format settings, CABAC : Yes
Format settings, ReFrames : 2 frames
Codec ID : avc1
Codec ID/Info : Advanced Video Coding
Duration : 2h 33mn
Bit rate mode : Variable
Bit rate : 2 206 Kbps
Maximum bit rate : 15.9 Mbps
Width : 1 280 pixels
Height : 534 pixels
Display aspect ratio : 2.35:1
Frame rate mode : Constant
Frame rate : 23.976 fps
Resolution : 24 bits
Colorimetry : 4:2:0
Scan type : Progressive
Bits/(Pixel*Frame) : 0.135
Stream size : 2.37 GiB (89%)
Writing library : x264 core 68 r1183M f21daff
Encoding settings : cabac=1 / ref=2 / deblock=1:0:0 / analyse=0x3:0x113 / me=hex / subme=4 / psy_rd=0.0:0.0 / mixed_ref=0 / me_range=16 / chroma_me=1 / trellis=1 / 8x8dct=1 / cqm=0 / deadzone=21,11 / chroma_qp_offset=0 / threads=3 / nr=0 / decimate=1 / mbaff=0 / bframes=3 / b_pyramid=0 / b_adapt=1 / b_bias=0 / direct=1 / wpredb=1 / keyint=250 / keyint_min=25 / scenecut=40 / rc=crf / crf=21.0 / qcomp=0.60 / qpmin=10 / qpmax=51 / qpstep=4 / ip_ratio=1.40 / pb_ratio=1.30 / aq=1:1.00
Encoded date : UTC 2009-10-29 22:12:01
Tagged date : UTC 2009-10-29 22:15:23

Can somebody point out what i'm doing wrong ?

[yaang]

Someone pointed out that my reference frames is set to 2 in the re-encoded version can it be the source of the problem ?

[poisondeathray]

Someone pointed out that my reference frames is set to 2 in the re-encoded version can it be the source of the problem ?

Very unlikely to be the cause

What device or software are you using to play? The re-encoded video doesn't have any vbv buffer. This should matter if on a PC with decent specs, but will be a problem on devices

What did you do with the audio? If you re-encoded and don't have a proper decoder that could explain why

What container? .mp4 ? .mkv ? If you don't have a proper splitter that might cause it

What happens with different media players? Try KMplayer or MPCHC or VLC

[yaang]

I'm using media player classic with k-lite mega codec pack.

Audio was converted to Nero AAC LC-256kbps multichannel but i tried with no audio too so that can't be the problem.

Container is .mp4

I tried re-encoding with tmpgenc xpress 4.0 with the same settings except i left the deinterlace method on deinterlace when necessary and it came out perfect. So i decided it's a deinterlacing issue. After i checked megui with this on mind i've noticed megui recognizes the video to be 23.976fps NTSC. I changed the output fps to be 29.97 and the problem was solved. I don't understand how that happened though since Gspot tell me video is 23.976 progressive. Is it possible for a video to be both progressive and interlaced ?