[FFmpeg-user] ffprobe only the first frame

[Mark Himsley]

I'd like to probe a file to get interlaced_frame="1" top_field_first="1" 
- which I believe is only available in -show_frames.

My file is 30 minutes log - I only want the data from the first frame.

I can't see anything in -h to answer this question. The ffmpeg -vframes, 
-frames:v and -t are not listed in ffprobe's help, and do not work.

Thanks in advance.



ffprobe -show_format -show_streams -show_frames -probesize 40000 
-print_format xml "tortoise.mxf"

ffprobe version N-41487-gee1748a Copyright (c) 2007-2012 the FFmpeg 
developers
   built on Jun 10 2012 17:04:40 with llvm_gcc 4.2.1 (Based on Apple 
Inc. build 5658) (LLVM build 2336.1.00)
   configuration: --prefix=/Users/mdsh/ffmpeg --arch=x86_64 
--enable-ffplay --enable-ffprobe --enable-shared --disable-indev=jack 
--enable-gpl --enable-nonfree --enable-pthreads --enable-libfaac 
--enable-libx264
   libavutil      51. 56.100 / 51. 56.100
   libavcodec     54. 25.100 / 54. 25.100
   libavformat    54.  6.101 / 54.  6.101
   libavdevice    54.  0.100 / 54.  0.100
   libavfilter     2. 78.101 /  2. 78.101
   libswscale      2.  1.100 /  2.  1.100
   libswresample   0. 15.100 /  0. 15.100
   libpostproc    52.  0.100 / 52.  0.100
[mxf @ 0x7fddb081ae00] Stream #0: not enough frames to estimate rate; 
consider increasing probesize
[mxf @ 0x7fddb081ae00] Stream #1: not enough frames to estimate rate; 
consider increasing probesize
Input #0, mxf, from 'tortoise.mxf':
   Metadata:
     timecode        : 10:53:51:04
   Duration: 00:28:21.92, start: 0.000000, bitrate: 42598 kb/s
     Stream #0:0: Video: mpeg2video (4:2:2), yuv422p, 720x608 [SAR 
608:405 DAR 16:9], 30000 kb/s, 25 tbr, 25 tbn, 50 tbc
     Stream #0:1: Audio: pcm_s16le, 48000 Hz, 4 channels, s16, 3072 kb/s
<?xml version="1.0" encoding="UTF-8"?>
<ffprobe>
     <frames>
         <frame media_type="video" key_frame="1" pkt_pts="0" 
pkt_pts_time="0.000000" pkt_dts="0" pkt_dts_time="0.000000" 
pkt_duration="1" pkt_duration_time="0.040000" pkt_pos="7168" width="720" 
height="608" pix_fmt="yuv422p" sample_aspect_ratio="608:405" 
pict_type="I" coded_picture_number="0" display_picture_number="0" 
interlaced_frame="1" top_field_first="1" repeat_pict="0" reference="3"/>
         <frame media_type="audio" key_frame="1" pkt_pts="0" 
pkt_pts_time="0.000000" pkt_dts="0" pkt_dts_time="0.000000" 
pkt_duration="1" pkt_duration_time="0.040000" pkt_pos="157696" 
sample_fmt="s16" nb_samples="1920"/>
...
goes on for a long time - you *really* don't want the uncut output ;-)

-- 
Mark