Share a piece of code, convert videos based on ffmpeg to pictures

The code is as follows:

function video2bmp (const strvideofilename, strsavepath:string): Boolean;var pfc1:pavformatcontext;  Pfc2:pavformatcontext;  Intvideostreamindex:integer;  Pps:ppavstream;  Iii:integer;  Pcc:pavcodeccontext;  Pcodec:pavcodec;  Pframevdo:pavframe;  Pframergb:pavframe;  Psc:pswscontext;  Avp:tavpacket;  Intremain:integer;  Bfirst:boolean;  Intdecoded:integer;  Intframefinished:integer;  Bmp:tbitmap;label lbexit;begin Result: = False;  {1. Register all container formats and codec} av_register_all ();  {2. Open file} pfc1: = nil; If Avformat_open_input (PFC1, Pansichar (ansistring (strvideofilename)), nil, nil) <> 0 THEN BEGIN ShowMessage (' Open Text Piece failed, please check your file!    ');  Exit;  End {3. Extracting stream information from a file} if Avformat_find_stream_info (PFC1, nil) < 0 THEN begin ShowMessage (' no audio or video streaming!    ');  Exit;  End  {4. Exhaustive all streams, find if video stream is included} Intvideostreamindex: =-1; PFC2: = PFC1;  PPS: = Pfc1^.streams;      For III: = 0 to Pfc1^.nb_streams-1 does begin if Pps^.codec.codec_type = Avmedia_type_video THEN BEGIN    Intvideostreamindex: = III;    End  Inc (PPS);  End If Intvideostreamindex =-1 THEN BEGIN ShowMessage (' There is no video stream!    ');  Exit;  End  {5. Navigate to the Video Stream} Inc (Pfc1^.streams, Intvideostreamindex);  PCC: = Pfc1^.streams^.codec;  Pcodec: = Avcodec_find_decoder (pcc^.codec_id);    If Pcodec = nil then begin ShowMessage (' Can't find video stream! ');  Exit;  End {6. Fix video Stream} if (Pcodec^.capabilities and codec_cap_truncated) = Codec_cap_truncated then pcc^.flags: = Pcc.flags or C  odec_flag_truncated;    If Avcodec_open2 (PCC, Pcodec, nil) < 0 THEN begin ShowMessage (' Open video stream error! ');  Exit;  End  {7. The video stream is converted to BMP} if (Pcc^.time_base.num >) and (Pcc^.time_base.den = 1) then Pcc^.time_base.den: = 1000;  PFRAMEVDO: = Avcodec_alloc_frame ();  Pframergb: = Avcodec_alloc_frame; {Output A picture by the original size of the video frame} avPicture_alloc (Pavpicture (PFRAMERGB), Av_pix_fmt_rgb32, pcc^. Width, pcc^.  Height); PSC: = Sws_getcontext (pcc^. Width, pcc^. Height, Pcc^.pix_fmt, pcc^. Width, pcc^.  Height, Av_pix_fmt_rgb32, sws_bicubic, nil, nil, nil);  Intremain: = 0;  Bfirst: = True;      {Look for each frame of video} while True does begin if Bfirst then BEGIN bfirst: = False;    Avp.data: = nil;    End While True does begin while Intremain > 0 does begin intdecoded: = Avcodec_decode_video2 (PCC, PFRAMEVDO        , intframefinished, @avp);        If intdecoded < 0 then break;        Dec (Intremain, intdecoded); {Find the full frame} if intframefinished <> 0 THEN begin {output by original} Sws_scale (PSC, @pFrameVdo ^ . Data, @pFrameVdo ^.linesize, 0, pcc^.          Height, @pFrameRGB ^.data, @pFrameRGB ^.linesize);          {Output bitmap} BMP: = Tbitmap.create; Try BMP.          PixelFormat: = Pf32bit; Bmp. Width: = pcc^.          Width; Bmp. Height: = pcc^. HEight For-III: = 0 to BMP. Height-1 do begin CopyMemory (BMP. SCANLINE[III], Pointer (Integer (pframergb.data[0]) + BMP. Width * 4 * III), BMP.          Width * 4);          End Bmp.          SaveToFile (Format ('%s\%d.bmp ', [Strsavepath, GetTickCount]));          Finally Bmp.free;          End          {Looking for Next frame}        Continue;      End      End      Repeat if Av_read_frame (PFC2, @avp) < 0 then Goto Lbexit;      Until Avp.stream_index = Intvideostreamindex;    Intremain: = avp.size;    End    Lbexit:avcodec_decode_video2 (PCC, PFRAMEVDO, intframefinished, @avp);    If Avp.data <> nil then av_free_packet (@avp);  If intframefinished = 0 then break;  End  {8. Releasing resources} sws_freecontext (PSC);  Avpicture_free (Pavpicture (PFRAMERGB));  Av_free (PFRAMERGB);  Av_free (PFRAMEVDO);  Avcodec_close (PCC);  Avformat_close_input (PFC1); {9. Return success} Result: = True;end;

Share a piece of code, convert videos based on ffmpeg to pictures