i am currently doing a video telephony application via ffmpeg and encountered a SIGSEGV whenever i increase my resolution<div>from QCIF to CIF or VGA. here is a backtrace:</div><div><br></div><div><div>Program received signal SIGSEGV, Segmentation fault.</div>
<div>[Switching to Thread 0xb0d77b70 (LWP 6549)]</div><div>0x01080b52 in x264_me_search_ref () from /usr/local/lib/libx264.so.83</div><div>(gdb) bt</div><div>#0 0x01080b52 in x264_me_search_ref () from /usr/local/lib/libx264.so.83</div>
<div>#1 0x01077f60 in ?? () from /usr/local/lib/libx264.so.83</div><div>#2 0x0107b049 in x264_macroblock_analyse () from /usr/local/lib/libx264.so.83</div><div>#3 0x010a34f2 in ?? () from /usr/local/lib/libx264.so.83</div>
<div>#4 0x010bf94b in ?? () from /usr/local/lib/libx264.so.83</div><div>#5 0x0109d5fb in ?? () from /usr/local/lib/libx264.so.83</div><div>#6 0x010a1441 in x264_encoder_encode () from /usr/local/lib/libx264.so.83</div>
<div>#7 0x00539b47 in ?? () from /usr/local/lib/libavcodec.so.52</div><div>#8 0x0806de81 in H264Encoder::EncodeFrame (this=0x8614498, </div><div> in=0xb0495008 "SSSTTTVVVWXXYYZZ[\\\\\\]]^^^__aaccdeeeefffggggfeefghijjjjkklll", 'm' <repeats 19 times>, "llkkkkllmmmmmmmm", 'l' <repeats 20 times>, "kkjjjjjjkklll", 'm' <repeats 13 times>, "nnoopooooooooonnmlkkkkkkkkkjjjjjjjj", 'k' <repeats 14 times>, "jjjjjjjkkkl"..., len=460800) </div>
</div><div><div><br></div><div>*H264Encoder::EncodeFrame is a function in my app</div><div><br></div><div>here is my encoding parameters:</div><div><div> ctx->rc_max_rate = (int) (((float)bitrate)*0.9/1000.0);</div>
<div> ctx->rc_min_rate = ctx->rc_max_rate;</div><div> ctx->rc_buffer_size = ctx->rc_max_rate;</div></div><div><div> ctx->intra_refresh = 1; //params.b_intra_refresh</div>
<div> ctx->sliced_threads = 1; //params.b_sliced_threads</div><div> ctx->me_range = 16; //analyse.i_me_range</div><div> ctx->qmin = 10; //rc.i_qp_min</div>
<div> ctx->qcompress = 0.6; //rc.f_qcompress</div><div> ctx->max_qdiff = 12; //rc.i_qp_step</div><div> ctx->b_quant_factor = 1.3; //minimum 1.26 params.rc.f_pb_factor</div>
<div> ctx->i_quant_factor = 1.4; //minimum 0.78 1/params.rc.f_ip_factor</div><div> ctx->max_b_frames = 0; //params.i_bframe </div><div> ctx->keyint_min = 10; //min-keyint</div>
<div> ctx->coder_type = 0; //params.b_cabac</div><div> ctx->gop_size = 60; //keyint or keyint_max</div><div> ctx->b_annexb = 0; //disable start code prefix</div>
<div> ctx->level = 30;</div><div> ctx->rtp_payload_size = MTU-100; //params.i_slice_max_size</div><div> ctx->weighted_p_pred = 0; //params.analyse.i_weighted_pred </div><div>
ctx->directpred = 1; //params.analyse.i_direct_mv_pred</div><div> ctx->flags |= CODEC_FLAG_PASS1; //PASS1 </div><div> ctx->flags &= ~CODEC_FLAG_4MV; //advanced prediction</div>
</div><div><br></div><div>whenever i disable b_intra_refresh, everything works perfectly. however i wanted to enable </div><div>intra_refresh as i see a huge performance boost with it on QCIF resolution. especially on a lossy network.</div>
<div><br clear="all">Kelvin Chua<br>
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