ffmpeg为视频添加时间戳

--enable-debug=3 --disable-doc --disable-optimizations --enable-pic --extra-cflags=-fPIC --enable-openssl --enable-libx264 --enable-libx265 --enable-gpl --enable-nonfree --enable-libfreetype

配置ffmpeg –enable-libfreetype 选项。

使用如下命令进行转码:

ffmpeg -i inputfile -vf "drawtext=fontfile=/usr/share/fonts/truetype/wqy/wqy-microhei.ttc: x=40: y=40: fontcolor=white: fontsize=100: box=1:boxborderw=20: boxcolor=0x00000000@1: text=%{n}" -vcodec libx264 -r 15  ./outputfilename.mkv

 

ffmpeg生成不同数据格式的像素rawdata

convert -size 128x128 xc:#ffffff ffffff_128_128.jpg

上面命令生成纯白图片。

ffmpeg  -pix_fmts | grep IO | awk '{print $2}' > pix_fmts_list

上面命令生成 pix format列表,删除开头无效行内容。

pix_fmts_list

echo "set -x" >> command.sh
cat pix_fmts_list | xargs -i echo "ffmpeg  -i ffffff_128_128.jpg  -pix_fmt {}   ffffff_128_128_{}.yuv" >> command.sh
chmod 777 command.sh

command

执行上面脚本,生成脚本的原因是因为方便跟踪出错的命令,也可以通过下面命令直接生成。

cat pix_fmts_list | xargs -i ffmpeg  -i ffffff_128_128.jpg  -pix_fmt {}   ffffff_128_128_{}.yuv

通过如下命令可使用ffplay进行播放rawdata 。

ffplay -f rawvideo -pixel_format gray  -video_size 128x128  fffff_128_128_gray.yuv

 

ffmpeg创建多个program的 ts流

 	
-program [title=title:][program_num=program_num:]st=stream[:st=stream...](output)
Creates a program withthe specified title, program_numand adds the specified stream(s)to it.

ffmpeg为视频添加多个音轨

使用上面生成的文件,配合如下命令:

ffmpeg -i ffffff_1920X1080.jpg -c:v libx265 ffffff_x265_1920x1080.ts

ffmpeg -i ffffff_with_audio.ts -i ffffff_x265_1920x1080.ts -map 0:0 -map 0:1 -map 1:0 -map 0:2 -c copy -program title=x264:program_num=1:st=0:st=1 -program title=x265:program_num=2:st=2:st=3 -f mpegts tow_program_audio.ts

Input #0, mpegts, from 'tow_program_audio.ts':
  Duration: 00:00:00.04, start: 1.400000, bitrate: 1203 kb/s
  Program 1 
    Metadata:
      service_name    : x264
      service_provider: FFmpeg
    Stream #0:0[0x100]: Video: h264 (High 4:4:4 Predictive) ([27][0][0][0] / 0x001B), yuvj444p(pc, progressive), 12x12 [SAR 1:1 DAR 1:1], 25 tbr, 90k tbn, 50 tbc
    Stream #0:1[0x101]: Audio: ac3 ([129][0][0][0] / 0x0081), 48000 Hz, mono, fltp, 96 kb/s
  Program 2 
    Metadata:
      service_name    : x265
      service_provider: FFmpeg
    Stream #0:2[0x102]: Video: hevc (Rext) (HEVC / 0x43564548), gray(tv), 1920x1080 [SAR 1:1 DAR 16:9], 25 tbr, 90k tbn, 25 tbc
    Stream #0:3[0x103]: Audio: aac (LC) ([15][0][0][0] / 0x000F), 48000 Hz, mono, fltp, 63 kb/s

 

ffmpeg为视频添加多个音轨

使用如下命令从图片生成ts视频,然后添加3个不同格式的音轨:

参考文章地址:

https://code-examples.net/zh-TW/q/b3bda2

convert -size 12x12 xc:#ffffff ffffff.jpg 
ffmpeg -i ffffff.jpg -c:v libx264 ffffff.ts
fmpeg -f lavfi -i "sine=frequency=1000:sample_rate=48000:duration=0.05" -c:a pcm_s16le test.wav
ffmpeg -f lavfi -i "sine=frequency=1000:sample_rate=48000:duration=0.05" -c:a ac3  test_ac3.ts
ffmpeg -f lavfi -i "sine=frequency=1000:sample_rate=48000:duration=0.05" -c:a aac  test_aac.ts
ffmpeg -i ffffff.ts -i test_ac3.ts -i test_aac.ts -i test.wav -map 0 -map 1 -map 2 -map 3 -codec copy -shortest ffffff_with_audio.ts

 

stream 对象创建时机

 
对于所有的文件格式,stream对象都是在probe函数探测到文件格式后调用相应的 AVInputFormat 的int (*read_header)(struct AVFormatContext *); 函数。

537 int avformat_open_input(AVFormatContext **ps, const char *filename,
 538                         AVInputFormat *fmt, AVDictionary **options)
 629 
 630     if (!(s->flags&AVFMT_FLAG_PRIV_OPT) && s->iformat->read_header)
 631         if ((ret = s->iformat->read_header(s)) < 0)
 632             goto fail;
For MKV
#0  avformat_new_stream (s=0x7fffe00008c0, c=0x0) at libavformat/utils.c:4456
#1  0x00000000007a1e89 in matroska_parse_tracks (s=0x7fffe00008c0) at libavformat/matroskadec.c:2199
#2  0x00000000007a4077 in matroska_read_header (s=0x7fffe00008c0) at libavformat/matroskadec.c:2657
#3  0x00000000008a1939 in avformat_open_input (ps=0x7fffe83b4d00, filename=0x423a060 "test.mkv", fmt=0x0, options=0x25e1410 <format_opts>) at libavformat/utils.c:631
For AVI 
#0  avformat_new_stream (s=0x7fffe00008c0, c=0x0) at libavformat/utils.c:4456
#1  0x000000000072970d in avi_read_header (s=0x7fffe00008c0) at libavformat/avidec.c:571
#2  0x00000000008a1939 in avformat_open_input (ps=0x7fffe83b4d00, filename=0x425a460 "/home/xw/Documents/videotest/mpeg1.avi", fmt=0x0, options=0x25e1410 <format_opts>) at libavformat/utils.c:631
For ts 
#0  avformat_new_stream (s=0x7fffe00008c0, c=0x0) at libavformat/utils.c:4456
#1  0x00000000007fd3b1 in pmt_cb (filter=0x7fffe0001040, section=0x7fffe0009500 "\002\260\027", section_len=26) at libavformat/mpegts.c:2075
#2  0x00000000007f8531 in write_section_data (ts=0x7fffe00174c0, tss1=0x7fffe0001040, buf=0x7fffe000f60d "\002\260\027", buf_size=183, is_start=1) at libavformat/mpegts.c:441
#3  0x00000000007fe2f1 in handle_packet (ts=0x7fffe00174c0, packet=0x7fffe000f608 "GO\377\020") at libavformat/mpegts.c:2394
#4  0x00000000007feb6e in handle_packets (ts=0x7fffe00174c0, nb_packets=26595) at libavformat/mpegts.c:2583
#5  0x00000000007ff1c3 in mpegts_read_header (s=0x7fffe00008c0) at libavformat/mpegts.c:2704
#6  0x00000000008a1939 in avformat_open_input (ps=0x7fffe83b4d00, filename=0x425d0f0 "/home/xw/Documents/videotest/tt.ts", fmt=0x0, options=0x25e1410 <format_opts>) at libavformat/utils.c:631
For mp3
#0  avformat_new_stream (s=0x7fffe00008c0, c=0x0) at libavformat/utils.c:4456
#1  0x00000000007ecf28 in mp3_read_header (s=0x7fffe00008c0) at libavformat/mp3dec.c:355
#2  0x00000000008a1939 in avformat_open_input (ps=0x7fffe83b4d00, filename=0x425d0f0 "/home/xw/Documents/videotest/tesss.mp3", fmt=0x0, options=0x25e1410 <format_opts>) at libavformat/utils.c:631

ffmpeg debug 调试configuration

configuration: --enable-debug=3 --disable-doc --disable-optimizations --enable-pic --extra-cflags=-fPIC --disable-demuxer=bluray --enable-openssl --enable-demuxer=dash

./configure --enable-debug=3 --disable-doc --disable-optimizations --enable-pic --extra-cflags=-fPIC --enable-openssl --enable-libx264 --enable-libx265 --enable-gpl --enable-nonfree