export LD_LIBRARY_PATH=/opt/ffmpeg/lib/
/opt/ffmpeg/bin/ffmpeg -i "/home/luoy/Videos/芳华.2017.TC720P独家高清中字.mp4" -ss 00:00:00 -t 00:00:01 -f image2 -y "./2_%04d.bmp"
ffmpeg version 3.4.1 Copyright (c) 2000-2017 the FFmpeg developers
built with gcc 5.4.0 (Ubuntu 5.4.0-6ubuntu1~16.04.6) 20160609
configuration: --enable-debug --enable-doc --disable-ffplay --enable-shared --enable-avresample --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-gpl --enable-libass --enable-libfreetype --enable-libvidstab --enable-libmp3lame --enable-libopenjpeg --enable-libopus --enable-libtheora --enable-libvorbis --enable-libvpx --enable-libx265 --enable-libxvid --enable-libx264 --enable-nonfree --enable-openssl --enable-libfdk_aac --enable-postproc --enable-small --enable-version3 --extra-cflags=-I/opt/ffmpeg/include --extra-ldflags=-L/opt/ffmpeg/lib --extra-libs=-ldl --prefix=/opt/ffmpeg
libavutil 55. 78.100 / 55. 78.100
libavcodec 57.107.100 / 57.107.100
libavformat 57. 83.100 / 57. 83.100
libavdevice 57. 10.100 / 57. 10.100
libavfilter 6.107.100 / 6.107.100
libavresample 3. 7. 0 / 3. 7. 0
libswscale 4. 8.100 / 4. 8.100
libswresample 2. 9.100 / 2. 9.100
libpostproc 54. 7.100 / 54. 7.100
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from '/home/luoy/Videos/芳华.2017.TC720P独家高清中字.mp4':
Metadata:
major_brand : isom
minor_version : 1
compatible_brands: isomavc1
creation_time : 2017-12-15T16:28:00.000000Z
encoder : Lite MP4 Tool v2.3
Duration: 02:09:09.24, start: 0.000000, bitrate: 1587 kb/s
Stream #0:0(und): Video: h264 (avc1 / 0x31637661), yuv420p, 1280x720, 1456 kb/s, 23.98 fps, 23.98 tbr, 24k tbn, 47.95 tbc (default)
Metadata:
creation_time : 2017-12-15T16:28:00.000000Z
handler_name : Imported with GPAC 0.4.6-DEV (internal rev. 5)
Stream #0:1(und): Audio: aac (mp4a / 0x6134706D), 44100 Hz, stereo, fltp, 127 kb/s (default)
Metadata:
creation_time : 2017-12-15T16:28:45.000000Z
handler_name : GPAC ISO Audio Handler
Stream mapping:
Stream #0:0 -> #0:0 (h264 (native) -> bmp (native))
Press [q] to stop, [?] for help
Output #0, image2, to './2_%04d.bmp':
Metadata:
major_brand : isom
minor_version : 1
compatible_brands: isomavc1
encoder : Lavf57.83.100
Stream #0:0(und): Video: bmp, bgr24, 1280x720, q=2-31, 200 kb/s, 23.98 fps, 23.98 tbn, 23.98 tbc (default)
Metadata:
creation_time : 2017-12-15T16:28:00.000000Z
handler_name : Imported with GPAC 0.4.6-DEV (internal rev. 5)
encoder : Lavc57.107.100 bmp
frame= 24 fps=0.0 q=-0.0 Lsize=N/A time=00:00:01.00 bitrate=N/A dup=1 drop=0 speed= 5.6x
video:64801kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: unknown

#include "libavcodec/avcodec.h"
#include "libavformat/avformat.h"
#include <stdio.h>
#include <stdarg.h>
#include <stdlib.h>
#include <string.h>
#include <inttypes.h>
#include <errno.h>
#include <stddef.h>
#include "libavutil/error.h"
int main(int argc, const char *argv[])
{
av_register_all();
int response = 0;
char *pchar;
// pchar = av_err2str(response);
return 0;
}

gcc -g -Wall -o build/hello_world -lz 0_hello_world.c
-lavformat -lavcodec -lswscale
-I/opt/ffmpeg/include -L/opt/ffmpeg/lib

gcc -g -Wall -o build/hello_world -lz 0_hello_world.c
-lavformat -lavcodec -lswscale
-I/opt/ffmpeg/include -L/opt/ffmpeg/lib
0_hello_world.c: In function ‘main’:
0_hello_world.c:16:9: warning: variable ‘pchar’ set but not used [-Wunused-but-set-variable]
char *pchar;
^
/usr/bin/ld: /tmp/ccgJJ9CV.o: undefined reference to symbol 'av_strerror@@LIBAVUTIL_55'
/opt/ffmpeg/lib/libavutil.so.55: error adding symbols: DSO missing from command line
collect2: error: ld returned 1 exit status
Makefile:10: recipe for target 'hello_world' failed
make: *** [hello_world] Error 1

$ echo $LD_LIBRARY_PATH
/opt/ffmpeg/lib: