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Hi Experts:<BR>
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plase help, thanks very much.<BR>
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Best Regards<BR> <BR>
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From: buyit@live.cn<BR>To: libav-user@ffmpeg.org<BR>Subject: question about libavcodec<BR>Date: Sun, 26 Feb 2012 22:19:38 +0800<BR><BR>
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<DIV dir=ltr><FONT size=4>Hi experts:</FONT><BR><FONT size=4></FONT> <BR><FONT size=4> i have some questions about the libavcodec.so: </FONT><BR> <BR><FONT size=4> 1. when compiling, how can i specify this library is compiled for ARM? and it includes NEON instruction supports? </FONT><BR><FONT size=4> 2. suppose ARCH_ARM and HAVE_NEON are defined, which i mentioned in question 1, does it mean this library can only be executed on ARM platform and the chipset must have NEON module? </FONT><BR><FONT size=4> 3. suppose the answer of quesion 2 is yes, then how can user choose libavcodec.so as they want? for example, there is an Android application "ROAMSAVE", it will use libavcodec.so, then how can i choose a suitable version libavcodec.so for roamsave? suppose i do not have any source code, and just want to download this library from internet?</FONT><BR><FONT size=4> 4. if the application roamsave together with a specific libavcodec run well on Samsung smart phone, and i am sure this version libavcodec support ARM and execute NEON instruction. but when i use them on another smart phone(Motorola), it crashs in libavcodec.so, the problem is alignment of second parameter of function ff_scalarproduct_int16_neon(), how can i find the root cause?the libavcodec runs NEON instruction well on Samsumg phone, so it means this library compiled with correct GCC version and can handle stack alignment well , right? but why it crashs because of alignment problem when run on another smart phone which also support NEON instruction? i am very confused about this issue, please help me, thanks very much. </FONT><BR><FONT size=4></FONT> <BR><FONT size=4>Best Regards </FONT><BR></DIV></DIV> </div></body>
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