The iOS streaming uses MRS to get stream from the TiVo, and then Stream hardware to transcode to H.264, so it's MRS based as well. So you're comparing apples and oranges.Īs I said, you can test multiple downloads at once pretty easily by starting 2 or more kmttg windows and downloading 1 show in each. Resume downloads is somewhat flaky but working with 20.4.1 and has been re-enabled in source code in preparation for next release. It seems to work best using "java downloads" mode, not curl, and you cannot enable "Use RPC to get NPL when possible" option if you want to use it, since RPC data doesn't have the byte offset needed for resume.Īpologies if this is not the right thread/forum. I need help with a problematic workflow that begins with kmttg and ends with Home Sharing videos from iTunes to my iPad. The videos, by design, wind up with closed captions in the form of soft subtitles. When I turn on the subtitles track while watching a video as it is streamed to the iPad, I get irritating pauses. It looks as if the scrubber bar has run out of buffered material at each pause point. If I turn off the subtitles, I can watch the video pause-free. So the act of turning on subtitles seems to bottleneck the stream at some point. I can't be sure where the bottleneck is located. #Subler hangs opening m4v tv#Īfter using kmttg to download, decrypt, and extract captions from a TV show, I use VideoReDo to manually do a QuickStream Fix and trim off the video's unwanted material. mpg file (in case I need it later) and then I also save it as a. Mp4 file, using an appropriate profile whose parameters (resolution, average bitrate, max bitrate, etc.) I have tried to adjust to get rid of the problem, with no success yet. srt file, the one containing the closed captions that kmttg created. I use a Mac utility called Subler for that. m4v file that I add to my iTunes library. I can stream that file to my iPad's Videos app via its Sharing capability. As I say, the play of the stream typically gets interrupted by unwanted pauses, but only when I tell the Videos app to show the soft subtitles. I have one video that I made some time ago using, if I remember correctly, HandBrake to both transcode. Mp4 and incorporate captions as soft subtitles. When I stream it while displaying soft subs, no pauses. But remaking it using the workflow I just described has given me a video with unwanted streaming pauses. I realize this could be an issue involving too high an average bitrate or too high a maximum bitrate, but it looks like it's not that simple. The video that does not pause has a slightly higher data rate, according to QuickTime Player, than the one that pauses: 2.44 Mbits/s vs. Of course, this does not tell me what the maximum bitrate is, so these things are quite hard to pin down.Īny help that anyone can give me insofar as how to further diagnose this problem and eventually triumph over it will be much appreciated. I made a very, very low bitrate version of the file alluded to above that streams fine until soft subs are turned on, but that tolerates soft subs in its earlier version that (I think) HandBrake made. This newer, "LBR" version has such a low bitrate that it exhibits macroblocking when played. Yet it still gives me streaming pauses when soft subs are on. So I looked at my router's traffic monitoring stats in Safari on my iPhone while the video was being streamed to my iPad. With subtitles off, the count of bytes being sent and received on the appropriate network connections edged up at a reasonable rate, in the tens of thousands every few seconds. But with subtitles on, those counts started shooting up by the tens of millions every few seconds. It looks like the data rate for the subtitles track itself is huge! Much greater than the data rate for the video track. That subtitles track was created by the Subler remux utility, based on a. srt file containing kmttg-derived closed captions. srt file into a "Tx3g" track in its output file. Subler says the subtitle track's visual settings use a normal size and also a scaled size of 960x81 pixels, in a file whose video resolution is 960x544. The offset of the subtitles is given as 0x462 pixels, and 462 + 81 is 543, near enough to 544. I'm going to try changing the scaled size to 240x20 with an offset of 0x524, to see if that reduces the overall data rate and wards off streaming pauses. The streaming pauses are just on the iPad and also on the iPhone.
0 Comments
Leave a Reply. |