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FFMPEG Corrupt output remuxing MP4 (Using API in C) -First file OK, 2nd file onwards is not
25 janvier, par RichardPI have a simple application written in C - it takes the video from a RTSP camera and just writes to disk in 1 minute segments. The first file created works fine, plays on anlmost anything. The Second file does not play. Programatically, The trace shows they are the same code flows, but I cant seem to find where the problem is to allow the 2nd file to be play exactly the same as the first.
There are frames in the 2nd file but they are random. The second file is created EXACTLY the same way as the first.
Any help from a guru would be greatly appreciated.
EDIT: FIX - The output duration needs to be set before the trailer is written.
int actual_duration = (int)difftime(time(NULL), start_time); for (int i = 0; i < output_ctx->nb_streams; i++) { output_ctx->streams[i]->duration = actual_duration * AV_TIME_BASE; } output_ctx->duration = actual_duration * AV_TIME_BASE; printf("DURATION = %d\r\n",output_ctx->duration); // Set the start_time for the output context output_ctx->start_time = 0; av_write_trailer(output_ctx);Code flow
Open RTSP Stream A: Create File n context Remux to file n Wait for minute to change Close File n context increment n Goto AMakefile
CC = gcc CFLAGS = -Wall -g LIBS = -lavformat -lavcodec -lavutil -lavdevice -lswscale -lavfilter -lavutil -lm -lz -lpthread TARGET = rtsp_remux all: $(TARGET) $(TARGET): rtsp_remux.o $(CC) -o $(TARGET) rtsp_remux.o $(LIBS) rtsp_remux.o: rtsp_remux.c $(CC) $(CFLAGS) -c rtsp_remux.c clean: rm -f $(TARGET) rtsp_remux.o .PHONY: all cleanrtsp_remux.c#includeavformat.h> #include time.h> #include #include #define OUTPUT_PREFIX "output" #define OUTPUT_EXTENSION ".mp4" #define MAX_FILES 4 int main(int argc, char *argv[]) { if (argc < 2) { fprintf(stderr, "Usage: %s \n", argv[0]); return -1; } const char *rtsp_url = argv[1]; AVFormatContext *input_ctx = NULL, *output_ctx = NULL; AVOutputFormat *output_fmt = NULL; AVPacket pkt; int ret, file_count = 0; char output_filename[1024]; time_t current_time; struct tm *timeinfo; int rename_lock = 0; avformat_network_init(); if ((ret = avformat_open_input(&input_ctx, rtsp_url, NULL, NULL)) < 0) { fprintf(stderr, "Could not open input file '%s'\n", rtsp_url); return -1; } if ((ret = avformat_find_stream_info(input_ctx, NULL)) < 0) { fprintf(stderr, "Failed to retrieve input stream information\n"); return -1; } av_dump_format(input_ctx, 0, rtsp_url, 0); while (file_count < MAX_FILES) { snprintf(output_filename, sizeof(output_filename), "%s_%03d%s", OUTPUT_PREFIX, file_count, OUTPUT_EXTENSION); if ((ret = avformat_alloc_output_context2(&output_ctx, NULL, NULL, output_filename)) < 0) { fprintf(stderr, "Could not create output context\n"); return -1; } output_fmt = output_ctx->oformat; for (int i = 0; i < input_ctx->nb_streams; i++) { AVStream *in_stream = input_ctx->streams[i]; AVStream *out_stream = avformat_new_stream(output_ctx, NULL); if (!out_stream) { fprintf(stderr, "Failed allocating output stream\n"); return -1; } if ((ret = avcodec_parameters_copy(out_stream->codecpar, in_stream->codecpar)) < 0) { fprintf(stderr, "Failed to copy codec parameters\n"); return -1; } out_stream->codecpar->codec_tag = 0; } if (!(output_fmt->flags & AVFMT_NOFILE)) { if ((ret = avio_open(&output_ctx->pb, output_filename, AVIO_FLAG_WRITE)) < 0) { fprintf(stderr, "Could not open output file '%s'\n", output_filename); return -1; } } if ((ret = avformat_write_header(output_ctx, NULL)) < 0) { fprintf(stderr, "Error occurred when opening output file\n"); return -1; } while (1) { current_time = time(NULL); timeinfo = localtime(¤t_time); if (timeinfo->tm_sec == 0 && !rename_lock) { rename_lock = 1; break; } else if (timeinfo->tm_sec != 0) { rename_lock = 0; } if ((ret = av_read_frame(input_ctx, &pkt)) < 0) break; AVStream *in_stream = input_ctx->streams[pkt.stream_index]; AVStream *out_stream = output_ctx->streams[pkt.stream_index]; pkt.pts = av_rescale_q_rnd(pkt.pts, in_stream->time_base, out_stream->time_base, AV_ROUND_NEAR_INF | AV_ROUND_PASS_MINMAX); pkt.dts = av_rescale_q_rnd(pkt.dts, in_stream->time_base, out_stream->time_base, AV_ROUND_NEAR_INF | AV_ROUND_PASS_MINMAX); pkt.duration = av_rescale_q(pkt.duration, in_stream->time_base, out_stream->time_base); pkt.pos = -1; if ((ret = av_interleaved_write_frame(output_ctx, &pkt)) < 0) { fprintf(stderr, "Error muxing packet\n"); break; } av_packet_unref(&pkt); } av_write_trailer(output_ctx); if (!(output_fmt->flags & AVFMT_NOFILE)) avio_closep(&output_ctx->pb); avformat_free_context(output_ctx); file_count++; } avformat_close_input(&input_ctx); avformat_network_deinit(); return 0; } I have tried changing to pointers, freeing and different things. I was expecting the 2nd file created to behave identically to the first.
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FFMPEG Video Multiplexer [closed]
24 janvier, par NaderI am a DirectShow developer, I used to build multiplexers that take 2 video inputs and generate one output, I would then use a video encoder mux to feed it the output + anothrr audio stream to generate the final video output. The multiplexer (DirectShow framework) allows me to process the input video from two sources (for example, adding effects using the two frames).
How can this can be done using FFMPEG?
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How to create thumbnail of a video using FFMpegCore ?
24 janvier, par l.diazborgI have a web application, where I need to create thumbnails or images taking the first frame of a video. There are already many examples of this, but I can't find anything that solves my problem. I am using this, but I'm finding it challenging, because I need to read the video and write the result using streams directly. This is my code:
var videoStream = file.OpenReadStream(); var outputStream = new MemoryStream(); FFMpegArguments .FromPipeInput(new StreamPipeSource(videoStream)) .OutputToPipe(new StreamPipeSink(outputStream), options => options .WithFrameOutputCount(1) .ForceFormat("jpeg") ) .ProcessSynchronously();Which leads me to the error:
Pipe is broken.According to here, the error is related to the fact that the output format cannot be known. Only by adding the.ForceFormat("opus")option does the error disappear, but I understand that theopusformat is for audio. Could any expert help me find the solution or tell me how I should do it? Thank you very much in advance.UPDATE
I found this answer where it explains how to correctly use ffmpeg pipes. I modified my code and now it is:
var videoStream = file.OpenReadStream(); var outputStream = new MemoryStream(); FFMpegArguments .FromPipeInput(new StreamPipeSource(videoStream)) .OutputToPipe(new StreamPipeSink(outputStream), opt => opt .Seek(TimeSpan.Zero) .Resize(650, 390) .WithFrameOutputCount(1) .WithVideoCodec(VideoCodec.Png) .ForceFormat("image2pipe") ) .ProcessSynchronously();The arguments indicated in the answer
ffmpeg -i - -ss 00:00:3 -s 650x390 -vframes 1 -c:v png -f image2pipe -are very similar to those generated by my code-i "\\.\pipe\FFMpegCore_9dd64" -ss 00:00:00.000 -s 650x390 -vframes 1 -c:v png -f image2pipe "\\.\pipe\FFMpegCore_997f4" -y, and even so, errors persists. -
ffmpeg "Time code of first frame" not making sense [closed]
23 janvier, par Kevin VaskoI can't seem to make sense of where ffmpeg is coming up with the "Time code of first frame" value.
My original file that I am using.
This video has the general timestamps of the original encoding date (aka the start time of the video the way I understanding it) and a duration of 8 min and 52s
$ mediainfo GL0100002_output.mp4 General Complete name : GL0100002_output.mp4 Format : MPEG-4 Format profile : Base Media Codec ID : isom (isom/iso2/avc1/mp41) File size : 93.7 MiB Duration : 8 min 52 s Overall bit rate : 1 476 kb/s Encoded date : UTC 2022-02-23 15:18:42 Tagged date : UTC 2022-02-23 15:18:42 Writing application : Lavf58.29.100 Video ID : 1 Format : AVC Format/Info : Advanced Video Codec Format profile : High@L3 Format settings : CABAC / 4 Ref Frames Format settings, CABAC : Yes Format settings, Reference frames : 4 frames Codec ID : avc1 Codec ID/Info : Advanced Video Coding Duration : 8 min 52 s Bit rate : 1 342 kb/s Width : 848 pixels Height : 480 pixels Display aspect ratio : 16:9 Frame rate mode : Constant Frame rate : 23.976 (24000/1001) FPS Color space : YUV Chroma subsampling : 4:2:0 Bit depth : 8 bits Scan type : Progressive Bits/(Pixel*Frame) : 0.138 Stream size : 85.2 MiB (91%) Title : GoPro AVC Writing library : x264 core 155 r2917 0a84d98 Encoding settings : cabac=1 / ref=3 / deblock=1:0:0 / analyse=0x3:0x113 / me=hex / subme=7 / psy=1 / psy_rd=1.00:0.00 / mixed_ref=1 / me_range=16 / chroma_me=1 / trellis=1 / 8x8dct=1 / cqm=0 / deadzone=21,11 / fast_pskip=1 / chroma_qp_offset=-2 / threads=12 / lookahead_threads=2 / sliced_threads=0 / nr=0 / decimate=1 / interlaced=0 / bluray_compat=0 / constrained_intra=0 / bframes=3 / b_pyramid=2 / b_adapt=1 / b_bias=0 / direct=1 / weightb=1 / open_gop=0 / weightp=2 / keyint=250 / keyint_min=23 / scenecut=40 / intra_refresh=0 / rc_lookahead=40 / rc=crf / mbtree=1 / crf=23.0 / qcomp=0.60 / qpmin=0 / qpmax=69 / qpstep=4 / ip_ratio=1.40 / aq=1:1.00 Language : English Encoded date : UTC 2022-02-23 15:18:42 Tagged date : UTC 2022-02-23 15:18:42 Color range : Full Codec configuration box : avcC Audio ID : 2 Format : AAC LC Format/Info : Advanced Audio Codec Low Complexity Codec ID : mp4a-40-2 Duration : 8 min 52 s Bit rate mode : Constant Bit rate : 129 kb/s Channel(s) : 2 channels Channel layout : L R Sampling rate : 48.0 kHz Frame rate : 46.875 FPS (1024 SPF) Compression mode : Lossy Stream size : 8.16 MiB (9%) Title : GoPro AAC Language : English Default : Yes Alternate group : 1 Encoded date : UTC 2022-02-23 15:18:42 Tagged date : UTC 2022-02-23 15:18:42 Other ID : 3 Type : Time code Format : QuickTime TC Duration : 8 min 52 s Frame rate : 23.976 (24000/1001) FPS Time code of first frame : 15:57:41:15 Time code, striped : Yes Title : GoPro AVC Language : English Default : No Encoded date : UTC 2022-02-23 15:18:42 Tagged date : UTC 2022-02-23 15:18:42Now if I run
ffmpeg -y -nostdin -v error -ss 00:00:00.042 -i GL0100002_output.mp4 -t 00:00:25.192 -map 0 -map -0:d -c:v libx264 -preset fast -crf 21 -c:a aac -sn GL0100002_test.DSME_0001.mp4I get the following mediainfo
$ mediainfo GL0100002_test.DSME_0001.mp4 General Complete name : GL0100002_test.DSME_0001.mp4 Format : MPEG-4 Format profile : Base Media Codec ID : isom (isom/iso2/avc1/mp41) File size : 4.54 MiB Duration : 25 s 234 ms Overall bit rate : 1 510 kb/s Writing application : Lavf58.29.100 Video ID : 1 Format : AVC Format/Info : Advanced Video Codec Format profile : High@L3 Format settings : CABAC / 4 Ref Frames Format settings, CABAC : Yes Format settings, Reference frames : 4 frames Codec ID : avc1 Codec ID/Info : Advanced Video Coding Duration : 25 s 234 ms Bit rate : 1 376 kb/s Width : 848 pixels Height : 480 pixels Display aspect ratio : 16:9 Frame rate mode : Constant Frame rate : 23.976 (24000/1001) FPS Color space : YUV Chroma subsampling : 4:2:0 Bit depth : 8 bits Scan type : Progressive Bits/(Pixel*Frame) : 0.141 Stream size : 4.14 MiB (91%) Title : GoPro AVC Writing library : x264 core 155 r2917 0a84d98 Encoding settings : cabac=1 / ref=2 / deblock=1:0:0 / analyse=0x3:0x113 / me=hex / subme=6 / psy=1 / psy_rd=1.00:0.00 / mixed_ref=1 / me_range=16 / chroma_me=1 / trellis=1 / 8x8dct=1 / cqm=0 / deadzone=21,11 / fast_pskip=1 / chroma_qp_offset=-2 / threads=12 / lookahead_threads=2 / sliced_threads=0 / nr=0 / decimate=1 / interlaced=0 / bluray_compat=0 / constrained_intra=0 / bframes=3 / b_pyramid=2 / b_adapt=1 / b_bias=0 / direct=1 / weightb=1 / open_gop=0 / weightp=1 / keyint=250 / keyint_min=23 / scenecut=40 / intra_refresh=0 / rc_lookahead=30 / rc=crf / mbtree=1 / crf=21.0 / qcomp=0.60 / qpmin=0 / qpmax=69 / qpstep=4 / ip_ratio=1.40 / aq=1:1.00 Language : English Color range : Full Codec configuration box : avcC Audio ID : 2 Format : AAC LC Format/Info : Advanced Audio Codec Low Complexity Codec ID : mp4a-40-2 Duration : 25 s 214 ms Duration_LastFrame : -3 ms Bit rate mode : Constant Bit rate : 129 kb/s Channel(s) : 2 channels Channel layout : L R Sampling rate : 48.0 kHz Frame rate : 46.875 FPS (1024 SPF) Compression mode : Lossy Stream size : 398 KiB (9%) Title : GoPro AAC Language : English Default : Yes Alternate group : 1 Other ID : 3 Type : Time code Format : QuickTime TC Duration : 25 s 234 ms Frame rate : 23.976 (24000/1001) FPS Time code of first frame : 15:57:41:15 Time code, striped : Yes Title : GoPro AVC Language : English Default : NoBut what I don't understand is where
Time code of first frameis coming from. I would expect it would be00:00:00.042or evenUTC 2022-02-23 15:18:42+ .042 but appear to be.Time code of first frame : 15:57:41:15Is this potentially clobbering together something to get this time that isn't obvious?
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reduce compression artifacts (using madVR as filter for ffmpeg ?) [closed]
23 janvier, par artifact4727madVR has a filter called 'reduce compression artifacts' which produces a very good quality output image on 'live playback'. I would like to permanently apply this filter to a video. Is it possible to use madVR as a filter for ffmpeg to generate a permanent output file? Thanks! madVR filter settings
