Hi, We are developing applications that allows one to stream video from any LAN device (e.g. computer, Android phone/tablet, etc) to an Android device.
Recently, we encountered a very strange problem on buffering and we believe the issue is possibly related to Android's platform/framework, i.e. lower level stuff. This video shows the problem we are experiencing http://hdmp4.com/TCC9302_STB_buffering_problem.3gp I have tested the same operation on 7" Samsung Galaxy Tab (Android 2.2), Nexus S (Android 2.3) and an Android setop box the one shown in the video). The issues is that when the STREAMING video exceeds a certain bitrate, the video either stops after 5-10 seconds, and then dies (or may continue playing for a few more seconds before dying) or it simply do not play at all. However, if I use an application that decodes the video by software decoding instead of hardware decoding. The video was able to play from start to the end without any problems. (due to slow CPU, arm11, 800mhz, video playback by software decoding as shown in the video link above actually lags but it does play fine.) I run the test streaming the video from a computer connected to the LAN via 100Mbps ethernet. All the test device are connected to the LAN via a b/g WIFI router. I can confirm that there is absolutely no problem with my network bandwidth and I can copy files from/to the computer to/from the Android device using ftp (using File Expert Application) at 16-24Mbps. (I get the live transfer bandwidth by looking at the software running at my computer which is monitoring my computer's network traffic.) I used the same mp4 test video encoded at different bitrate. The resolution of the streaming video does not matter because I can reproduce this using a 720x480 video as well. All the Android devices I have tested suffer the same problem. The Android STB suffers from this problem when video bitrate exceeds about 10Mbps. 7" Samsung Galaxy Tab suffers from this problem when video bitrate is at or exceeds 6Mbps. Nexus S suffers from this problem when video bitrate is at or exceeds 3Mbps. >From these results, it is obvious that this is related to the Android OS or the chip used. If the same video is being played locally from the device's SDcard, there is no such buffering problem, even at several times the bitrate compared to when it is streamed. We have no idea what is going on here and are seeking solutions. I can perform more tests and report here if you can tell me what/how to do the test as a non-programmer (I can't code). However, from our test (or apparent in the video), it seems to me that Android OS is dumping the buffer and then refilling it for no obvious reason. This only occurs when hardware decoding was used. Software decoding does not have any buffering problems. This means the problem is definitely not related to bandwidth and most likely related to hardware decoding buffering. For lower bitrate video, we do not see this problem at all. We are also interested to hire developers who can fix this problem for us, preferably at the application but fixing this at the OS level is also fine.. Please e-mail me directly if you are capable of fixing this problem and available for hire. Otherwise, please provide your opinion on this issue. (I have searched online but did not see anyone encountering this problem. Maybe because no one have tried streaming such high bitrate video yet..) Thanks Eric -- You received this message because you are subscribed to the Google Groups "Android Developers" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/android-developers?hl=en
