mp4 skipping problem in mpc

[yukukuhi]

i have raw avi files, i convert it to mp4 using megui

when i try to seek/skip the converted mp4 files in mpc, the timeline is running but the video stucks and comes after 8 secs.

not all mp4 files stucks only the converted mp4

my pc configuration

windows 8 pro
i5 processor 3.2 ghz
4gb ram

please help

[KarMa]

Use mediainfo to look at the video with the problem, and then post what it outputs here.

I tend to believe it has to do with large GOPs or open/closed GOPs.

[yukukuhi]

General
Complete name : C:\Users\Ganesh Kumaresh\Documents\AVerRecord_160620_212409a-muxed.mp4
Format : MPEG-4
Format profile : Base Media
Codec ID : isom (isom/avc1)
File size : 106 MiB
Duration : 2mn 22s
Overall bit rate mode : Variable
Overall bit rate : 6 259 Kbps
Encoded date : UTC 2016-06-22 16:37:19
Tagged date : UTC 2016-06-22 16:37:19

Video
ID : 1
Format : AVC
Format/Info : Advanced Video Codec
Format profile : High@L4.1
Format settings, CABAC : Yes
Format settings, ReFrames : 3 frames
Codec ID : avc1
Codec ID/Info : Advanced Video Coding
Duration : 2mn 22s
Bit rate mode : Variable
Bit rate : 6 000 Kbps
Maximum bit rate : 14.0 Mbps
Width : 1 920 pixels
Height : 1 080 pixels
Display aspect ratio : 16:9
Frame rate mode : Constant
Frame rate : 25.000 fps
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 8 bits
Scan type : MBAFF
Scan type, store method : Interleaved fields
Scan order : Top Field First
Bits/(Pixel*Frame) : 0.116
Stream size : 102 MiB (96%)
Writing library : x264 core 148 r2638 7599210
Encoding settings : cabac=1 / ref=4 / deblock=1:0:0 / analyse=0x3:0x133 / me=umh / subme=9 / psy=1 / psy_rd=1.00:0.00 / mixed_ref=1 / me_range=24 / chroma_me=1 / trellis=2 / 8x8dct=1 / cqm=0 / deadzone=21,11 / fast_pskip=0 / chroma_qp_offset=-2 / threads=6 / lookahead_threads=1 / sliced_threads=0 / slices=4 / nr=0 / decimate=1 / interlaced=tff / bluray_compat=1 / constrained_intra=0 / bframes=3 / b_pyramid=1 / b_adapt=2 / b_bias=0 / direct=3 / weightb=1 / open_gop=1 / weightp=0 / keyint=250 / keyint_min=1 / scenecut=40 / intra_refresh=0 / rc_lookahead=60 / rc=2pass / mbtree=1 / bitrate=6000 / ratetol=1.0 / qcomp=0.60 / qpmin=0 / qpmax=69 / qpstep=4 / cplxblur=20.0 / qblur=0.5 / vbv_maxrate=14000 / vbv_bufsize=14000 / nal_hrd=vbr / filler=0 / ip_ratio=1.40 / aq=1:1.00
Encoded date : UTC 2016-06-22 16:37:19
Tagged date : UTC 2016-06-22 16:37:26
Color range : Limited
Color primaries : BT.709
Transfer characteristics : BT.709
Matrix coefficients : BT.709

Audio
ID : 2
Format : AAC
Format/Info : Advanced Audio Codec
Format profile : LC
Codec ID : 40
Duration : 2mn 22s
Bit rate mode : Variable
Bit rate : 256 Kbps
Maximum bit rate : 265 Kbps
Channel(s) : 2 channels
Channel positions : Front: L R
Sampling rate : 48.0 KHz
Frame rate : 46.875 fps (1024 spf)
Compression mode : Lossy
Stream size : 4.34 MiB (4%)
Encoded date : UTC 2016-06-22 16:10:33
Tagged date : UTC 2016-06-22 16:37:26

[sneaker]

What version of MeGUI are you using? There are known problems with the mp4box some older versions come with. Switch to the MeGUI development update server in settings.
What player are you using exactly? MPC, MPC-HC or MPC-BE? What splitter? I recommend latest LAV Splitter (included in latest MPC-HC).

For greatest compatibility I would recommend to turn open gop off when targeting mp4 container.

[yukukuhi]

i'm using MeGUI_2624_x86 and mpc-hc

[LigH.de]

Max. keyframe distance: 250 frames. MPC-HC set up to seek rather exactly than fast ... in the worst case, it has to decode silently from almost 250 frames before your desired seek position before it can continue playing.

You can switch MPC-HC options to prefer fast seeking; this will seek only to GOP starts (which may be about 10 seconds apart), but at least it will play immediately.

If you want finer GOPs, then limit the maximum GOP size to way less than 250 frames (e.g. Blu-ray compatible H.264 encoding will do so); but this will reduce the compressibility, so expect slightly larger files with the same CRF, or slightly worse quality with the same target bitrate.

[hello_hello]

I just tried a quick test encode and setting bluray_compat=1 seems to force keyint_min=1.
Don't enable the Bluray Compatibility option in the encoder configuration unless you're encoding to make a complaint Bluray video disc, and even if you are, select "Bluray" as the target playback device in the drop down list in MeGUI's encoder configuration (under the Main tab) instead of fiddling with x264's advanced settings yourself. If you're not needing Bluray compatibility, load the x264 defaults and adjust the speed preset and tuning etc but don't play with the advanced settings unless you know you need to.

When you're not using the Bluray compatibility option....
MeGUI has two keyint modes. When the "GOP calculation" setting is set to "FPS based", MeGUI uses the following formula to set the max and min key intervals.

Specified max gop size / 25 * frame rate = actual maximum gop size.

Specified min gop size / 25 * frame rate = actual minimum gop size.

Using the above formula, if you set max and min to 250 and 25 (the MeGUI defaults) and the frame rate is 24fps, the following would happen:

250 / 25 * 24 = max key-int 240

25 / 25 * 24 = min key-int 24

So you'd end up with --keyint 240 and --min-keyint 24 for a 24fps video.

If you want to use specific keyint values, change the "GOP calculation" setting to "fixed" and you'll probably have to disable the Bluray Compatibility option.

Having said all that the keyint minimum value won't have anything to do with seeking. A large keyint maximum value might, but personally I wouldn't change it. Leave the keyint settings in MeGUI's x264 encoder configuration at their defaults, and leave the "GOP calculation" setting to "FPS based". MeGUI will ensure the max keyint setting is 10x the frame rate and min keyint is the same as the frame rate, unless you select Bluray as the target playback device, in which case it'll change them accordingly.

For the seeking problem, check MPC-HC is set for "fast seek" under "Tweaks" in it's preferences, and as suggested, try disabling "open gop" in MeGUI's x264 encoder configuration (if you load the x264 defaults open-gop will be disabled).

[yukukuhi]

@hello_hello
Thanks for your help, it solved the problem.