[Libav-user] about ffmpeg source code and api version

Hi, I downloaded ffmpeg source code long time ago. And I find there are various versions of ffmpeg api and related documentation. How to know api version of my downloaded source code? Below information maybe helpful: git branch -a * master remotes/origin/HEAD - origin/master

[Libav-user] How to set display and sample aspect ratio in stream

Hi, I use ffmpeg to encode video/audio and mux video/audio streams into one files. How to set display and sample aspect ratio for video stream? Thanks! B.R. Andrew___ Libav-user mailing list Libav-user@ffmpeg.org

Re: [Libav-user] dts/pts generated by aac encoder less than zero

process? Can I discard those packets with negative pts/dts? Thanks! B.R. Andrew At 2015-10-09 16:49:57, "Hendrik Leppkes" <h.lepp...@gmail.com> wrote: >On Fri, Oct 9, 2015 at 7:53 AM, qw <applema...@163.com> wrote: >> Hi, >> >> I use avcodec_enco

[Libav-user] dts/pts generated by aac encoder less than zero

Hi, I use avcodec_encode_audio2() to call aac encoder to compress audio. AVFrame::pts is set to 0 for 1st frame, 1 for 2nd frame, 2 for 3rd frame, and so on. But I find pts and dts are negtive values in 1st two output packets, and 3rd packet's pts/dts is 0. Why pts and dts are less than 0 in

[Libav-user] one error message produced by mov

Hi, I'm confused with below source code. http://ffmpeg.org/doxygen/trunk/movenc_8c_source.html#l02214 http://ffmpeg.org/doxygen/2.6/movenc_8c_source.html#l02211 In mov_write_mdhd_tag(), there is one condition I'm really confused: if (version != 0 && track->mode == MODE_MOV) {

Re: [Libav-user] dts/pts generated by aac encoder less than zero

? Thanks! B.R. Andrew At 2015-10-09 16:49:57, "Hendrik Leppkes" <h.lepp...@gmail.com> wrote: >On Fri, Oct 9, 2015 at 7:53 AM, qw <applema...@163.com> wrote: >> Hi, >> >> I use avcodec_encode_audio2() to call aac encoder to compress audio. >>

[Libav-user] How to encode aac coded packets with priming samples and remainder samples to keep av sync

Hi, I'm want to mux video and audio packets into one mp4 file, where aac is used as audio encoder. https://developer.apple.com/library/mac/documentation/QuickTime/QTFF/QTFFAppenG/QTFFAppenG.html As the above link shows, aac encoder has priming samples at the start and remainder samples in

[Libav-user] force I frame in video coding

Hi, In general, avcodec_encode_video2() is used to encode each video frame. How to force encoder code current frame as I frame? Thanks! B.R. andrew___ Libav-user mailing list Libav-user@ffmpeg.org http://ffmpeg.org/mailman/listinfo/libav-user

Re: [Libav-user] dts/pts/duration in packets

of output packets. How to handle this case? Thanks! B.R. Andrew 在 2015-09-02 14:34:55，"Max Vlasov" <max.vla...@gmail.com> 写道： On Wed, Sep 2, 2015 at 6:01 AM, qw <applema...@163.com> wrote: I'm using avcodec_encode_video2() and avcodec_encode_audio2() to encode vid

[Libav-user] which function has the function of pixel format conversion

Hi, There are too many ffmpeg functions. I want to find one function, which can convert one pixel format into another, and the argument is AVFrame. Does ffmpeg has this kind of function? Thanks! B.R. Andrew___ Libav-user mailing list

[Libav-user] which function has the function of pixel format conversion

Hi, There are too many ffmpeg functions. I want to find one function, which can convert one pixel format into another for video data, and the argument is AVFrame. Does ffmpeg has this kind of function? Thanks! B.R. Andrew ___ Libav-user

[Libav-user] performance issue about audio decoding

Hi, I intend to use avcodec_decode_audio4(). below is url link of the function description: http://ffmpeg.org/doxygen/2.6/group__lavc__decoding.html#ga834bb1b062fbcc2de4cf7fb93f154a3e where, decoder will allocate a buffer for decoded frame. Does it mean, decoder will allocate a buffer

[Libav-user] timestamp for avcodec_encode_audio2()

Hi, The parameter I set is incorrect. I have no problem now. Thanks! Andrew Hi, I use avcodec_encode_video2() to encode video, which can produce pts/dts based on codec time base. But when I use avcodec_encode_audio2() to encode audio frames, and audio codec is AV_CODEC_ID_AAC, I

Re: [Libav-user] force I frame in video coding

equest seems odd to me since if you encode P or B frames as I frame you will get... P or B frame, hence partial image. I've never done this, I can't tell you how to do this, sorry. Good luck! Le 2 sept. 2015 à 10:33, qw <applema...@163.com> a écrit : Hi, In general, avcodec_encode_vide

[Libav-user] how to read av packet based on time stamp

Hi, Below is the description of av_read_frame(), which returns the next frame of a stream. http://ffmpeg.org/doxygen/2.6/group__lavf__decoding.html#ga4fdb3084415a82e3810de6ee60e46a61 And I have one question about av_read_frame(). I expect av_read_frame() returns av packet with smaller

[Libav-user] how to convert pts/dts to value in normal time unit

Hi, In AVPacket, pts/dts and duration is in AVStream->time_base units. Does ffmpeg provide some function that can convert those timestamps into value in the unit of second or millisecond? Thanks! B.R. Andrew___ Libav-user mailing list

[Libav-user] one issue about audio resampler

Hi, I'm using below functions to implement audio resampling, but encounter one issue. swr_alloc_set_opts(), swr_init(), swr_convert_frame(), swr_get_delay(). Input frame is set to 8000hz mono AV_SAMPLE_FMT_FLT, while output frame is set to 44100Hz mono AV_SAMPLE_FMT_S16, and output frame's

[Libav-user] How to read audio/video samples based on timestamp instead of position and timestamp

Hi, In mov.c, there is one function, i.e. 'static AVIndexEntry *mov_find_next_sample(AVFormatContext *s, AVStream **st)', which get audio/video samples in terms of position and timestamp. In general, this function will output samples chunk by chunk. But I want ffmpeg output samples only

[Libav-user] qlv format

Hi, I just find a new format, namely qlv. Does ffmpeg support qlv? Thanks! B.R. Andrew___ Libav-user mailing list Libav-user@ffmpeg.org http://ffmpeg.org/mailman/listinfo/libav-user

[Libav-user] how to encode avframe as jpeg format

Hi, Long time ago, PIX_FMT_YUVJ420P is used as input format to jpeg encoder. Current ffmpeg version suggests 'PIX_FMT_YUVJ420P planar YUV 4:2:0, 12bpp, full scale (JPEG), deprecated in favor of PIX_FMT_YUV420P and setting color_range'. If PIX_FMT_YUV420P is used as input format, how to set

Re: [Libav-user] qlv format

qlv files can be downloaded from below website: http://v.qq.com/ At 2015-09-19 02:57:00, "Paul B Mahol" <one...@gmail.com> wrote: >On 9/18/15, qw <applema...@163.com> wrote: >> Hi, >> >> >> I just find a new format, namely qlv. Does

[Libav-user] the difference between mjpeg in ffmpeg and libjpeg

Hi, JPEG has adopted many standards. There are several jpeg codec in ffmpeg, such as mjpeg, mjpegb, ljpeg, jpegls. libjpeg is another open source of jpeg codec. what's difference between mjpeg in ffmpeg and libjpeg? Does libjpeg support all JPEG standards/algorithms? In libjpeg, jpeg encoder

[Libav-user] how to get correct frame rate in video stream

Hi, AVStream is the structure that contain stream information, including frame rate and samples. r_frame_rate is guessed value, that maybe field rate or frame rate. avg_frame_rate is average frame rate. which one can be used to get video frame rate? if not, how to get accurate frame rate?

[Libav-user] does ffmpeg support ssim for yuv and rgb colorspace

Hi, Does ffmpeg support ssim for yuv and rgb colorspace? Thanks! B.R. Andrew ___ Libav-user mailing list Libav-user@ffmpeg.org http://ffmpeg.org/mailman/listinfo/libav-user

[Libav-user] Could not find tag for codec pcm_s16be in stream using ffmpeg

Hi, I built ffmpeg in my PC, and confirmed my built ffmpeg supported pcm_s16be codec using the command of 'ffmpeg -codecs | grep pcm_s16be'. ffmpeg -codecs | grep pcm_s16be ffmpeg version 2.6.2 Copyright (c) 2000-2015 the FFmpeg developers built with gcc 4.1.2 (GCC) 20080704 (Red Hat

[Libav-user] How to decode only 2d video from 3d content

Hi, As I know, H.264 MVC allows decoder is only able to decode base view for 3d video. How to only get 2d video via ffmpeg lib? Thanks! B.R. andrew ___ Libav-user mailing list Libav-user@ffmpeg.org http://ffmpeg.org/mailman/listinfo/libav-user

[Libav-user] how to get metadata via ffmpeg/ffprobe command line

Hi, As I know, source file may have metadata, so does each stream. I use ffprobe to print some information of 'wynonna_earp.mp4 '. But how to printf its metadata in json format? ffprobe wynonna_earp.mp4 ffprobe version 2.8.3 Copyright (c) 2007-2015 the FFmpeg developers built with icc

[Libav-user] how to know whether disk is full or not

Hi, If disk is full, does ffmpeg provide some functions to report full-disk error? Thanks! B.R. Andrew ___ Libav-user mailing list Libav-user@ffmpeg.org http://ffmpeg.org/mailman/listinfo/libav-user

[Libav-user] how to predict the size of destination clips

Hi, Does ffmpeg provide some function that can predict the size of destination clips before transcoding? Thanks! B.R. Andrew ___ Libav-user mailing list Libav-user@ffmpeg.org http://ffmpeg.org/mailman/listinfo/libav-user

[Libav-user] how to use two rtmp plugins in ffmpeg

Hi, ffmpeg has its own built-in rtmp plugin, and also support to use rtmpdump as another rtmp plugin. How to use specified rtmp plugin, i.e. build-in rtmp plugin or rtmpdump plugin, if rtmpdump is enabled and built within ffmpeg? Thanks! Regards Andrew

Re: [Libav-user] how to parse audio/video information for rtmp protocal

//Can av_dump_format anwser your question? thanks for your help. It's the function that i want. At 2016-06-29 11:20:17, "Steven Liu" <lingjiujia...@gmail.com> wrote: 2016-06-29 10:58 GMT+08:00 qw <applema...@163.com>: Hi, FFmpeg has its native rtmp plugin, and

[Libav-user] how to build ffmpeg with -O0 instead of -O1

Hi, I want to build ffmpeg without optimization options, which means compiling flags uses O0 instead of O1-O3. I use the following command to build ffmpeg, where O1 is used in config.mak. ./configure --enable-debug --disable-optimizations .. I want to disable all optimization options to

[Libav-user] one question about multi-thread usage in filter graph

Hi, There are two functions about filter graph: int av_buffersrc_add_frame_flags ( AVFilterContext * buffer_src, AVFrame * frame, int flags ) int av_buffersink_get_frame ( AVFilterContext * ctx, AVFrame * frame )

Re: [Libav-user] what is the relationship between fontsize and image resolution in drawtext filter

in width and height? Thanks! At 2016-04-26 17:20:13, "Nicolas George" <geo...@nsup.org> wrote: >L'octidi 8 floréal, an CCXXIV, qw a écrit : >> I want to use drawtext filter to put some string on video stream. What is >> the relationship between fontsize and imag

[Libav-user] what is the relationship between fontsize and image resolution in drawtext filter

Hi, I want to use drawtext filter to put some string on video stream. What is the relationship between fontsize and image resolution in drawtext filter? If fontsize is set to 20, what is the height and width of rendered text? Thanks! B.R. Andrew

[Libav-user] how to get text_h and text_w from vf_drawtext

Hi, http://ffmpeg.org/doxygen/2.8/vf__drawtext_8c.html#a65f3f8df0fa6740ed48a631c89cde373 static int filter_frame(AVFilterLink *inlink, AVFrame *frame) In the end of the above function, text_w and text_h are shown, which are stored in DrawTextContext:var_values[VAR_TEXT_W] and

[Libav-user] how to get text_h and text_w in drawtext filter

Hi, 'drawtext filter' is used to put some utf-8 format text over video stream. I want to get two values, i.e. text_h and text_w, which will be used in c/c++ functions. As I know, drawtext filter is indeed libfreetype. How to get those two values? Does libfreetype have some interface

Re: [Libav-user] what is the relationship between fontsize and image resolution in drawtext filter

of UTF-8 encoded characters? Does ffmpeg have some functions to support it? At 2016-04-26 19:56:51, "Nicolas George" <geo...@nsup.org> wrote: >L'octidi 8 floréal, an CCXXIV, qw a écrit : >> libfreetype is used to draw text on video stream. > >Yes, I know

[Libav-user] which filter is used to produce fake yuv image

Hi, http://ffmpeg.org/ffmpeg-filters.html I want to use some filter to produce one specified yuv/rgb image, and render text on that image via drawtext filter later in filter graph. Then run the filter graph, and get text_h and text_w from 'ff_vf_drawtext'. which filter is used to produce fake

Re: [Libav-user] does filter graph support multi-thread

, "Nicolas George" <geo...@nsup.org> wrote: >Le quintidi 5 prairial, an CCXXIV, qw a écrit : >> ffmpeg supports filter graph. Does filter graph support multi-thread? or >> it can only be called in single thread, and I must make multi-thread >> program based on filt

[Libav-user] why ffmpeg reports error when decoding rm or rmvb files

Hi, I'm using the following command to decode some rm and rmvb files, and ffmpeg reports error as shown below: [root@PT-18376 test-clips]# ffmpeg -i hanma.rm -xerror -f null /dev/null ffmpeg version 2.8.3 Copyright (c) 2000-2015 the FFmpeg developers built with icc (ICC) 14.0.2 20140120

[Libav-user] how to know via ffmpeg lib whether disk is full or not

Hi, In some rare case, when there are huge AV transcoding tasks, disk will become full if old files are not deleted immediately. Then those transcoding tasks can't work correctly. In general transcoding application, av_interleaved_write_frame() and av_read_frame() are used to make media

[Libav-user] why ffmpeg reports error when decoding rm or rmvb files

Hi, I'm using the following command to decode some rm and rmvb files, and ffmpeg reports error as shown below: [root@PT-18376 test-clips]# ffmpeg -i hanma.rm -xerror -f null /dev/null ffmpeg version 2.8.3 Copyright (c) 2000-2015 the FFmpeg developers built with icc (ICC) 14.0.2 20140120

[Libav-user] Is ffmpeg able to decode h264 SVC bitstream

Hi, ffmpeg has incorported openh264, and is able to produce h.264 svc bitstream. Can ffmpeg decode svc bitstream? Thanks! B.R. Andrew ___ Libav-user mailing list Libav-user@ffmpeg.org http://ffmpeg.org/mailman/listinfo/libav-user

[Libav-user] where to get test clips

Hi, I have made one program, which is able to transcode different kinds of video files into specified container, such as mp4 and flv. And I want to get as many sort of test clips as possible in order to test my program. Where to get test clips to test my program? Thanks! B.R. Andrew

[Libav-user] why ffmpeg reports error when decoding rm or rmvb files

Hi, I'm using the following command to decode some rm and rmvb files, and ffmpeg reports error as shown below: [root@PT-18376 test-clips]# ffmpeg -i hanma.rm -xerror -f null /dev/null ffmpeg version 2.8.3 Copyright (c) 2000-2015 the FFmpeg developers built with icc (ICC) 14.0.2 20140120

[Libav-user] how to know whether AVFrame is audio frame or video frame

Hi, how to know whether AVFrame is audio frame or video frame? Thanks! B.R. Andrew ___ Libav-user mailing list Libav-user@ffmpeg.org http://ffmpeg.org/mailman/listinfo/libav-user

[Libav-user] what is difference between av_dup_packet() and av_copy_packet()

Hi, What's the difference between av_dup_packet() and av_copy_packet()? How to use both functions? Thanks! B.R. Andrew___ Libav-user mailing list Libav-user@ffmpeg.org http://ffmpeg.org/mailman/listinfo/libav-user

[Libav-user] how to disable all concealing upon decoding audio/video stream

Hi, I use ffmpeg or ffmpeg lib to parse and decode mp4 and rmvb file, for some of which some concealment log will be shown on screen as follows: [rv40 @ 0x16579e0] concealing 3440 DC, 3440 AC, 3440 MV errors in B frame [rv40 @ 0x1804860] concealing 3440 DC, 3440 AC, 3440 MV errors in B frame

[Libav-user] how to set filter's name in filter graph

Hi, I define the following filter graph: setpts=PTS-STARTPTS, fps=fps=20.00, scale=500:280; drawtext="fontfile=/usr/share/fonts/truetype/freefont/FreeSerif.ttf: text='Test Text'" And avfilter_graph_parse_ptr(), and avfilter_graph_config() are used to create filter graph. How to set the name

[Libav-user] where to get HD AV clips to test

Hi, I'm developping transcoding application based on ffmpeg lib, and evaluating the qulaity of video/audio codec. Where can I get HD quality 4K and 1080p clips with above 10Mbps bitrate? Look forward to relpy! Thanks! Regards Andrew ___

[Libav-user] one questions about the usage of av_frame_ref() and av_frame_unref()

Hi, I have one question about the usage of av_frame_ref() and av_frame_unref(). For avcodec_decode_video2(), the following url is its description: http://ffmpeg.org/doxygen/3.1/group__lavc__decoding.html#ga3ac51525b7ad8bca4ced9f3446e96532 When AVCodecContext.refcounted_frames is set to 1, the

[Libav-user] how to build ffmpeg lib for android and ios platform

Hi, I know the steps of building ffmpeg lib on linux. However, how to build ffmpeg lib for android and ios platform? Thanks! Regards andrew ___ Libav-user mailing list Libav-user@ffmpeg.org http://ffmpeg.org/mailman/listinfo/libav-user

[Libav-user] what's the general setting for network reading and writing?

Hi, If input or output is set to file, it's easy to set AVFormatContext. But for network application, there are many issues that should be considered, such as network delay, no network connection, and corrupted data. How to set AVFormatContext to deal with those general network issues?

[Libav-user] One question about timeout in rtmp

Hi, I use native rtmp in ffmpeg 3.1.1 to demuxer rtmp stream from nginx server. avformat_open_input() is used to open input rtmp stream. Native rtmp plugin supports 'timeout' option as shown below: -timeout .D.. Maximum timeout (in seconds) to wait for incoming

[Libav-user] how to deal with network timeout

Hi, I'm making program to read and write rtmp stream to server. Many ffmpeg functions are related in network operation, such as connection, read and write: avformat_open_input(), avformat_find_stream_info(), av_read_frame(), and av_interleaved_write_frame(). If network is not good,

[Libav-user] one question about network blocking issue

Hi, I'm making program to read and write rtmp av stream. If network is bad, some ffmpeg functions will block indefinitely. The rtmp application will use the following functions, including avformat_open_input(), avformat_find_stream_info(), avformat_alloc_output_context2(), avio_open(),

[Libav-user] does ffmpeg support AEC?

Hi, Does ffmpeg support AEC, i.e. Acoustic Echo Cancellation? Or Does ffmpeg has third-party dependency lib that supports AEC? Thanks! Regards Andrew___ Libav-user mailing list Libav-user@ffmpeg.org http://ffmpeg.org/mailman/listinfo/libav-user

[Libav-user] which rtmpdump is beter for fmpeg's native rtmp lib and rtmpdump

Hi, I found ffmpeg support two rtmp libs, where one is ffmpeg's native rtmp lib, and the other is rtmpdump. Which is better? Thanks! Regards Andrew___ Libav-user mailing list Libav-user@ffmpeg.org http://ffmpeg.org/mailman/listinfo/libav-user

[Libav-user] how to parse audio/video information for rtmp protocal

Hi, FFmpeg has its native rtmp plugin, and also can use rtmpdump instead if enable-librtmp is chosen when building ffmpeg. I have reviewed rtmp specification, where client and server can notify its peer of audio/video information via metadata message, and of audio/video codec via connect

Re: [Libav-user] where to get HD AV clips to test

ou find 4k clips (without sound unfortunately), just scroll down. https://media.xiph.org/video/derf/ I hope this helps. Best regards Felix Gesendet: Donnerstag, 04. August 2016 um 13:45 Uhr Von: qw <applema...@163.com> An: libav-user@ffmpeg.org Betreff: [Libav-user] where to get HD AV

[Libav-user] is it possible to set buffer time of demuxer

Hi, I use ffmpeg lib to do transcoding, where input and output are both rtmp url links. If ffmpeg lib is too slow sometimes, the transcoding program will terminate in the middle. Is it possible to set or get buffer time of demuxer? Thanks! Regards

[Libav-user] how to set timeout in rtmp plugin to avoid indefinite waiting?

Hi, ffmpeg 2.8.6 is used to develop application, which reads rtmp stream and does some video processing. 'AVIOInterruptCB interrupt_callback' is used to avoid indefinite waiting if there is no avpackets in network. But it doesn't work, and avformat_open_input() waits forever. My source code

Re: [Libav-user] how to set timeout in rtmp plugin to avoid indefinite waiting?

hi Marlon Mirchevski, How to submit my solution/update for the ticket issue? Thanks! Regards Andrew 在 2016-11-08 18:28:19，"Marlon Mirchevski" <n...@point.com.mk> 写道： On 27.10.2016 13:01, qw wrote: Hi, ffmpeg 2.8.6 is used to develop application, which reads rtmp strea

[Libav-user] where to find the latest version of rtmp specification

Hi, I have read the source code of native rtmp plugin in ffmpeg, and find there are some rtmp messages that don't exist in rtmp specification v1.0, such as onBWDone(). where can I get the latest version of rtmp specification that corresponds to ffmpeg's rtmp plugin? Thanks! Regards

[Libav-user] how to get video bitrate and frame rate from flv file

Hi, I have one question about parsing encoding information from flv file. How to get video bitrate and frame rate from flv file? Thanks! Regards andrew___ Libav-user mailing list Libav-user@ffmpeg.org

[Libav-user] how to send av packets to rtmp server when changing encoding setting

Hi, I have one question about sending rtmp stream. If audio/video encoding settings are not changed, I can send only once one data message of '@setDataFrame', one audio message of 'AAC sequence header', and one video message of 'AVC sequence header'. But I want to change audio or video

[Libav-user] where to get flv specification

Hi, I'm reading muxer 'flv' and demuxer 'flv'/'live_flv'. Where can I get the latest flv specification? Thanks! Regards Andrew ___ Libav-user mailing list Libav-user@ffmpeg.org http://ffmpeg.org/mailman/listinfo/libav-user

[Libav-user] how to send new metadata to rtmp stream by flv muxer

Hi, I have one question about ffmpeg lib usage. If rtmp url link is used as input and ouput address, then flv muxer/demuxer and rtmp plugin will be chosen to process av stream. At the beginning, one onMetaData message will be sent to output rtmp stream. But in the middle of time, I want to

[Libav-user] how to update av encoding setting realtimely

Hi, ffmpeg native rtmp plugin is used to receive and send in and out rtmp stream respectively. If I want to change frame rate or bit rate in the middle of session, which ffmpeg functions are used to send the changed av encoding setting via rtmp stream? Thanks! Regards Andrew

[Libav-user] how to use specified h.264 decoder first

Hi, I use the same method as transcoding.c to initialize AVFormatContext: http://ffmpeg.org/doxygen/2.8/transcoding_8c_source.html First, avformat_open_input() is called, and avformat_find_stream_info() is called later. avformat_find_stream_info() will detect, open, and close video codec and

[Libav-user] how to convert mkv into mp4 with hevc video

Hi, source file link: https://drive.google.com/open?id=0Bx1RhuOwoy_HQ3hNVlZQdmtYY28 The source mkv file is shown as follows: ffprobe version 2.8.6 Copyright (c) 2007-2016 the FFmpeg developers built with icc (ICC) 14.0.2 20140120 configuration: --cc=/opt/intel/bin/icc --enable-version3

[Libav-user] where to get vc1 sample clips

Hi, Do you know where to get av sample clips with VC1 video encoding? Thanks! Regards Andrew___ Libav-user mailing list Libav-user@ffmpeg.org http://ffmpeg.org/mailman/listinfo/libav-user

[Libav-user] does ffmpeg support libjpeg-turbo

Hi, Does ffmpeg support libjpeg-turbo? Thanks! Regards Andrew___ Libav-user mailing list Libav-user@ffmpeg.org http://ffmpeg.org/mailman/listinfo/libav-user

[Libav-user] can ffmpeg support add audio/video stream dynamically

Hi, I have one question about ffmpeg's one key function. If ffmpeg fetch one rtmp stream from one rtmp server and no audio stream is available at the beginning, then ffmpeg only detect video stream without audio stream. However, after several minutes, one audio stream existed in rtmp stream,

[Libav-user] does ffmpeg have some video filters that support multiple-video-streams overlay

Hi, I have checked ffmpeg supported filters, where overlay can put one video on the top of another, and amix can mix multiple audio streams into one stream. Is there any video filter that can put images from several video streams on the top of one video stream image? Thanks! Regards

Re: [Libav-user] can ffmpeg support add audio/video stream dynamically

m does ffmpeg support the above cases? At 2017-07-12 14:18:27, "Steven Liu" <lingjiujia...@gmail.com> wrote: >2017-07-10 20:24 GMT+08:00 qw <applema...@163.com>: >> Hi, >> >> I have one question about ffmpeg's one key function. If ffm

[Libav-user] can protocol async support to check/get time delay

Hi, http://www.ffmpeg.org/ffmpeg-protocols.html#async I have one question about the usage of protocol async in ffmpeg. As we know, protocol async is to decouple I/O operation from demux thread. In realtime application, if demux thread is too slow, how can I know how much delay there is?

[Libav-user] does ffmpeg lib have the function of creating av sync stream

Hi, I have one question about ffmpeg lib usage. Does ffmpeg lib have the function of creating av sync stream? Thanks! Regards Andrew ___ Libav-user mailing list Libav-user@ffmpeg.org http://ffmpeg.org/mailman/listinfo/libav-user

[Libav-user] there is no ts adjustment after bsf filter

Hi, I have written some audio/video bsf filter, which changes avpacket's dts/pts. But in the function of output_packet() in ffmpeg.c, there is no adjustment before calling write_packet() if my bsf filter is used. Is it a potential bug in ffmpeg? Thanks Regards

[Libav-user] where is the logic of calculate output frame's pts in h264 decoder

Hi, I'm reading ffmpeg source code. where is the logic of calculate output frame's pts in h264 decoder? Thanks! Regards Andrew___ Libav-user mailing list Libav-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/libav-user To unsubscribe, visit

[Libav-user] is avio_write() thread-safe

Hi, I have one question: Is avio_write() thread-safe? Are those functions thread-safe, i.e. fprintf() and fflush() ? Thanks! Regard Andrew___ Libav-user mailing list Libav-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/libav-user To

[Libav-user] does mpegts muxer/demuxer support metadata

Hi, Mpeg 2 transport stream supports several ways to send and receive metadata. Does mpegts demuxer/muxer support metadata? which tools does mepgts demuxer/muxer support to transport metadata? Thanks! Regards Andrew___ Libav-user mailing list

[Libav-user] does flv muxer support timestamp wrap around

Hi, I have read flv standard, which support timestamp wrap around, where packet's timestamp can reset to zero sometime, and increases as normal again. Does ffmpeg's flv muxer support the feature? Thanks! Regards Andrew___ Libav-user mailing

[Libav-user] one question about movenc.c

Hi, I have one question about movenc.c: https://github.com/FFmpeg/FFmpeg/blob/master/libavformat/movenc.h#L116 What does it mean, i.e. 'active picture (w/o VBI) height for D-10/IMX' ? And, what is D-10/IMX? Thanks! Regards Andrew ___

[Libav-user] one question about get_buffer2/get_format in ffmpeg.c

Hi, In ffmpeg.c, input stream's deocder will be initialized in init_input_stream(), where ist->dec_ctx->get_format and ist->dec_ctx->get_buffer2 are custom-defined functions, i.e. get_format() and get_buffer(). Why ffmpeg.c uses custom-defined functions instead of default functions? I add

[Libav-user] does ffmpeg/dnn filters support text/face recognition

Hi, ffmpeg has supported dnn filters, i.e. dnn_classify/dnn_detect/dnn_processing, according to http://ffmpeg.org/ffmpeg-filters.html. Does those filters support text/face recognition? Thanks! Regards Andrew___ Libav-user mailing list