开源组的大神，我的问题回答一下？seek 4k视频卡死 2

我用http能流畅的播放本地3s的4k视频，但是当我一个seek拖动，就卡死了，跟踪发现一个3s的4k视频，当seek后，在不定发送get请求，get分段请求多达395个（例如：Range: bytes=76731894- .... Range: bytes=76958016- Range: bytes=78386072-），为啥不发送一个
Range: bytes=xxxx- 请求？这是为什么？请大神解释一下？

下边是视频信息
General
Complete name : mov_20174k.mp4
Format : MPEG-4
Format profile : QuickTime
Codec ID : qt 0000.00 (qt )
File size : 83.1 MiB
Duration : 13 s 410 ms
Overall bit rate mode : Variable
Overall bit rate : 52.0 Mb/s
Encoded date : UTC 2017-06-13 02:29:54
Tagged date : UTC 2017-06-13 02:30:08
Writing library : Apple QuickTime
com.apple.quicktime.location.ISO6709 : +22.5303+113.9385+013.461/
com.apple.quicktime.make : Apple
com.apple.quicktime.model : iPhone SE
com.apple.quicktime.software : 9.3.5
com.apple.quicktime.creationdate : 2017-06-13T10:29:53+0800

Video
ID : 1
Format : AVC
Format/Info : Advanced Video Codec
Format profile : High@L5.1
Format settings, CABAC : Yes
Format settings, ReFrames : 1 frame
Format settings, GOP : M=1, N=30
Codec ID : avc1
Codec ID/Info : Advanced Video Coding
Duration : 13 s 410 ms
Bit rate : 51.9 Mb/s
Width : 3 840 pixels
Height : 2 160 pixels
Display aspect ratio : 16:9
Rotation : 90°
Frame rate mode : Variable
Frame rate : 29.970 (29970/1000) FPS
Minimum frame rate : 28.571 FPS
Maximum frame rate : 30.000 FPS
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 8 bits
Scan type : Progressive
Bits/(Pixel*Frame) : 0.209
Stream size : 82.9 MiB (100%)
Title : Core Media Video
Encoded date : UTC 2017-06-13 02:29:54
Tagged date : UTC 2017-06-13 02:30:08
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 : 13 s 408 ms
Source duration : 13 s 468 ms
Bit rate mode : Variable
Bit rate : 86.6 kb/s
Channel(s) : 1 channel
Channel positions : Front: C
Sampling rate : 44.1 kHz
Frame rate : 43.066 FPS (1024 spf)
Compression mode : Lossy
Stream size : 142 KiB (0%)
Source stream size : 142 KiB (0%)
Title : Core Media Audio
Encoded date : UTC 2017-06-13 02:29:54
Tagged date : UTC 2017-06-13 02:30:08

Other #1
Type : meta
Duration : 13 s 410 ms
Bit rate mode : CBR

Other #2
Type : meta
Duration : 13 s 410 ms
Bit rate mode : CBR

这是关键帧信息：
key_frame:NO:0 pts:0 dts:0 diff_pts:0
key_frame:NO:1 pts:600 dts:600 diff_pts:600
key_frame:NO:2 pts:1201 dts:1201 diff_pts:601
key_frame:NO:3 pts:1801 dts:1801 diff_pts:600
key_frame:NO:4 pts:2402 dts:2402 diff_pts:601
key_frame:NO:5 pts:3002 dts:3002 diff_pts:600
key_frame:NO:6 pts:3603 dts:3603 diff_pts:601
key_frame:NO:7 pts:4203 dts:4203 diff_pts:600
key_frame:NO:8 pts:4804 dts:4804 diff_pts:601
key_frame:NO:9 pts:5404 dts:5404 diff_pts:600
key_frame:NO:10 pts:6004 dts:6004 diff_pts:600
key_frame:NO:11 pts:6605 dts:6605 diff_pts:601
key_frame:NO:12 pts:7205 dts:7205 diff_pts:600
key_frame:NO:13 pts:7806 dts:7806 diff_pts:601
frame key_frame:14 nb_frames:402

视频测试地址：https://pan.baidu.com/s/1gf7oRwJ

No source file, entry point, or test is identified in the report. Start by reproducing the seek freeze with the linked 4K MP4 and inspect the player’s HTTP range-request and seek path. Done means determining why hundreds of range requests are issued and providing a verified fix or a documented explanation.

Written by the indexing model from the issue text.