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Rennes Emotion Map 2010-11
19 octobre 2011, par
Mis à jour : Juillet 2013
Langue : français
Type : Texte
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H.264 muxing to MP4 from CCTV (HW) encoder using ffmpeg library in C / C++, how to fetch AVCodecContext::extradata
26 mai 2016, par DomI am trying to mux a video to mp4 file from packets received via SDK API of CCTV camera. The stream from CCTV seems to consist of packets of h264 I and P-frames only (no B-frames).
The problem is, that the file is not playable in Daum PotPlayer when I leave the AVCodecContext::extradata empty, however, I can play the file in VLC. If I feed the extra data (probably not correctly - I just copy the first 50 bytes from the packet received from the HW encoder), the file is playable in PotPlayer, but not in VLC.
I do not know, how to prepare the extradata properly.
The code below shows the muxing.
void WriteVideo()
{
AVFormatContext* formatContext = nullptr;
AVStream* stream = nullptr;
int ret = 0;
ret = avformat_alloc_output_context2(&formatContext, nullptr, "mp4", OUTPUT_V_FILE_NAME);
if (ret < 0)
{
fprintf(stderr, "Error occurred when allocating output context: %d\n", ret);
return;
}
stream = avformat_new_stream(formatContext, nullptr);
if (!stream)
{
avformat_free_context(formatContext);
formatContext = nullptr;
fprintf(stderr, "Error occurred creating new stream");
return;
}
stream->codec->codec_tag = 0;
if (formatContext->oformat->flags & AVFMT_GLOBALHEADER)
{
stream->codec->flags |= CODEC_FLAG_GLOBAL_HEADER;
}
stream->codec->codec_type = AVMEDIA_TYPE_VIDEO;
stream->codec->codec_id = AV_CODEC_ID_H264;
stream->codec->pix_fmt = AV_PIX_FMT_YUV420P;
stream->codec->bit_rate = 4096000; // 8192000; // 4096000; // 384000;
stream->codec->width = 1920; // 352
stream->codec->height = 1080; // 288
stream->codec->gop_size = 50;
AVRational tb;
tb.num = 1;
tb.den = 25;
stream->codec->time_base = tb;
//stream->codec->field_order = AVFieldOrder::AV_FIELD_UNKNOWN;
//stream->codec->color_primaries = AVColorPrimaries::AVCOL_PRI_BT470BG;
//stream->codec->color_trc = AVColorTransferCharacteristic::AVCOL_TRC_GAMMA22;
//stream->codec->colorspace = AVColorSpace::AVCOL_SPC_BT470BG;
//stream->codec->chroma_sample_location = AVChromaLocation::AVCHROMA_LOC_CENTER;
AVRational aratio;
aratio.num = 1;
aratio.den = 1;
stream->codec->sample_aspect_ratio = aratio;
// stream->codec->delay = 0;
// stream->codec->color_range = AVColorRange::AVCOL_RANGE_MPEG;
av_dump_format(formatContext, 0, formatContext->filename, 1);
if (!(formatContext->oformat->flags & AVFMT_NOFILE))
{
if (avio_open(&formatContext->pb, formatContext->filename, AVIO_FLAG_WRITE) < 0)
{
avformat_free_context(formatContext);
formatContext = nullptr;
fprintf(stderr, "Error occurred when opening output file.");
return;
}
}
avformat_write_header(formatContext, nullptr);
int frameIdx = 0;
int pts = 0;
int dts = 0;
int pkt_pos = 0;
int size = static_cast<int>(tmpRawFrameBuffer.size());
AVPacket pkt = { 0 };
av_init_packet(&pkt);
while (frameIdx < size)
{
pkt.data = tmpRawFrameBuffer[frameIdx];
pkt.size = tmpRawFrameSizes[frameIdx];
// debug purphose start
FILE* f;
char filename[MAX_PATH];
sprintf_s(filename, MAX_PATH, OUTPUT_PACKET_FILE_PATTERN_NAME, frameIdx);
auto err = fopen_s(&f, filename, "wb");
if (err != 0)
{
fprintf(stderr, "Could not open %s\n", OUTPUT_V_FILE_NAME);
exit(1);
}
fflush(stdout);
fwrite(pkt.data, 1, pkt.size, f);
fclose(f);
// debug purphose end
if (tmpRawFrameTypes[frameIdx] == VIDEO_I_FRAME)
{
pkt.flags |= AV_PKT_FLAG_KEY;
stream->codec->extradata_size = 50;
stream->codec->extradata = (uint8_t*)av_malloc(stream->codec->extradata_size);
memcpy(stream->codec->extradata, pkt.data, stream->codec->extradata_size);
}
pkt.pts = pts++;
pkt.dts = dts++;
/* rescale output packet timestamp values from codec to stream timebase */
// av_packet_rescale_ts(&pkt, stream->codec->time_base, stream->time_base);
pkt.pts = av_rescale_q(pkt.pts, stream->codec->time_base, stream->time_base);
pkt.dts = av_rescale_q(pkt.dts, stream->codec->time_base, stream->time_base);
pkt.duration = 512; // should be calculated (derived from FPS 25, and 12800)
pkt.pos = -1;
pkt.stream_index = stream->index;
auto ret = av_write_frame(formatContext, &pkt);
if (ret < 0)
{
fprintf(stderr, "Error while writing video frame: %d\n", ret);
break;
}
av_packet_unref(&pkt);
++frameIdx;
}
if (formatContext)
{
av_write_trailer(formatContext);
if (!(formatContext->oformat->flags & AVFMT_NOFILE)) avio_close(formatContext->pb); // close the output file
avformat_free_context(formatContext);
formatContext = nullptr;
}
}
</int>It seems, the packet from camera (buffered in tmpRawFrameBuffer vector) contains some headers, but I am not able to parse them, I do not understand the meaning of the header.
The first bytes of the I-frame packet looks like the dump bellow :
00 00 01 FC 02 19 F0 87 A0 23 73 41 B6 C0 01 00
00 00 00 01 67 4D 00 2A 95 A8 1E 00 89 F9 61 00
00 03 00 01 00 00 03 00 32 84 00 00 00 01 68 EE
3C 80 00 00 00 01 06 E5 01 19 80 00 00 00 01 65
B8 00 00 08 C7 B0 23 FF F7 80 EE FE 63 B6 FB F5
...The first bytes of the first P-frame :
00 00 01 FD E5 24 00 00 00 00 00 01 61 E0 22 27
FF D6 B0 D7 A4 2B 71 6B 19 C5 87 CA BB 8B BF 60
14 59 B4 00 CC BC 0F C0 9E FD 84 B5 FB C4 83 DB
5A 8B 80 FC EC D6 33 6D DE 10 96 6F 31 41 86 5C
D4 22 F9 33 48 5B CE 77 38 17 0C D6 DD C7 6C E8
...first bytes of next P-frame :
00 00 01 FD 5E 2F 00 00 00 00 00 01 61 E0 42 2F
FF E7 06 DD 3C 66 26 15 94 93 7A F1 30 8A 6D B8
AD DD 6B 0F 38 89 1D 1B 5C AC 44 6A D7 D1 21 3B
E2 29 F8 14 BB 98 1C 06 4D B6 10 BB DB B9 CA 4F
0B ED B1 A9 06 78 8C EC 06 6D 9F 4F 79 0C 35 5B
......
begining of next I-frame :
00 00 01 FC 02 19 F0 87 A2 23 73 41 75 89 01 00
00 00 00 01 67 4D 00 2A 95 A8 1E 00 89 F9 61 00
00 03 00 01 00 00 03 00 32 84 00 00 00 01 68 EE
3C 80 00 00 00 01 06 E5 01 1B 80 00 00 00 01 65
B8 00 00 0F 07 F0 7F F6 6C 69 43 0F F0 28 DF 97
...Does anybody know, how to fill correctly the extradata ? I just made a copy of first 50 bytes, but it seems, this is not correct.
Probably the headers are (AUD)(SPS)(PPS)(I-Slice)(PPS)(P-Slice)(PPS)(P-Slice) ... (AUD)(SPS)(PPS)(I-Slice) (http://stackoverflow.com/a/20686267/1699328), however, I do not know, how to extract data for the
stream->codec->extradataI tried to get some inspiration in this post H.264 muxed to MP4 using libavformat not playing back, but I am not able to figure out what are values of spsFrameLen, ppsFrameLen and spsFrame.
The result of the muxer (first and last bytes of the mp4 file) :
00 00 00 20 66 74 79 70 69 73 6F 6D 00 00 02 00
69 73 6F 6D 69 73 6F 32 61 76 63 31 6D 70 34 31
00 00 00 08 66 72 65 65 00 26 2E 6D 6D 64 61 74
00 00 00 0D FC 02 19 F0 87 A0 23 73 41 B6 C0 01
00 00 00 00 16 67 4D 00 2A 95 A8 1E 00 89 F9 61
00 00 03 00 01 00 00 03 00 32 84 00 00 00 04 68
EE 3C 80 00 00 00 05 06 E5 01 19 80 00 01 C0 87
65 B8 00 00 08 C7 B0 23 FF F7 80 EE FE 63 B6 FB
F5 97 A8 6B 48 39 61 99 FD 99 27 41 F2 78 54 EE
D1 38 8E E8 18 DD 05 E4 BA F4 EB 69 CF 91 5C 34
...
...
...
95 B8 D8 D4 C3 AF A1 BA AC 28 F0 D4 D4 7C 48 9A
0C A6 8C 4C 98 00 00 05 1E 6D 6F 6F 76 00 00 00
6C 6D 76 68 64 00 00 00 00 00 00 00 00 00 00 00
00 00 00 03 E8 00 00 13 B0 00 01 00 00 01 00 00
00 00 00 00 00 00 00 00 00 00 01 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 01 00 00 00 00 00
00 00 00 00 00 00 00 00 00 40 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 02 00 00 04 48 74 72 61
6B 00 00 00 5C 74 6B 68 64 00 00 00 03 00 00 00
00 00 00 00 00 00 00 00 01 00 00 00 00 00 00 13
B0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 01 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 01 00 00 00 00 00 00 00 00 00 00 00 00 00
00 40 00 00 00 07 80 00 00 04 38 00 00 00 00 00
24 65 64 74 73 00 00 00 1C 65 6C 73 74 00 00 00
00 00 00 00 01 00 00 13 B0 00 00 00 00 00 01 00
00 00 00 03 C0 6D 64 69 61 00 00 00 20 6D 64 68
64 00 00 00 00 00 00 00 00 00 00 00 00 00 00 32
00 00 00 FC 00 55 C4 00 00 00 00 00 2D 68 64 6C
72 00 00 00 00 00 00 00 00 76 69 64 65 00 00 00
00 00 00 00 00 00 00 00 00 56 69 64 65 6F 48 61
6E 64 6C 65 72 00 00 00 03 6B 6D 69 6E 66 00 00
00 14 76 6D 68 64 00 00 00 01 00 00 00 00 00 00
00 00 00 00 00 24 64 69 6E 66 00 00 00 1C 64 72
65 66 00 00 00 00 00 00 00 01 00 00 00 0C 75 72
6C 20 00 00 00 01 00 00 03 2B 73 74 62 6C 00 00
00 93 73 74 73 64 00 00 00 00 00 00 00 01 00 00
00 83 61 76 63 31 00 00 00 00 00 00 00 01 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 07 80
04 38 00 48 00 00 00 48 00 00 00 00 00 00 00 01
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 18 FF FF 00 00 00 2D 61 76 63 43 01 4D 00 2A
FF E1 00 16 67 4D 00 2A 95 A8 1E 00 89 F9 61 00
00 03 00 01 00 00 03 00 32 84 01 00 04 68 EE 3C
80 00 00 00 18 73 74 74 73 00 00 00 00 00 00 00
01 00 00 00 7E 00 00 02 00 00 00 00 1C 73 74 73
73 00 00 00 00 00 00 00 03 00 00 00 01 00 00 00
33 00 00 00 65 00 00 00 34 73 74 73 63 00 00 00
00 00 00 00 03 00 00 00 01 00 00 00 3B 00 00 00
01 00 00 00 02 00 00 00 37 00 00 00 01 00 00 00
03 00 00 00 0C 00 00 00 01 00 00 02 0C 73 74 73
7A 00 00 00 00 00 00 00 00 00 00 00 7E 00 01 C0
C7 00 00 24 EE 00 00 2F 67 00 00 1D 83 00 00 2E
8F 00 00 30 B6 00 00 2F 44 00 00 2F 50 00 00 34
6B 00 00 30 BE 00 00 31 0C 00 00 31 E7 00 00 30
EA 00 00 31 4E 00 00 31 A8 00 00 32 21 00 00 31
E6 00 00 31 B5 00 00 31 14 00 00 31 AF 00 00 31
9D 00 00 33 60 00 00 32 11 00 00 32 4C 00 00 31
F0 00 00 32 91 00 00 43 43 00 00 44 29 00 00 44
EC 00 00 44 20 00 00 44 86 00 00 45 AD 00 00 47
47 00 00 46 9F 00 00 46 D9 00 00 47 BE 00 00 48
CD 00 00 3E 50 00 00 40 98 00 00 41 0E 00 00 40
43 00 00 41 07 00 00 41 BB 00 00 41 FF 00 00 30
5E 00 00 33 C7 00 00 34 B7 00 00 33 F1 00 00 33
0D 00 00 32 DB 00 01 89 86 00 00 3B E1 00 00 3C
55 00 00 3C 64 00 00 3C B7 00 00 3C FD 00 00 3E
54 00 00 3E C5 00 00 3E 1C 00 00 3E 94 00 00 3E
44 00 00 3E D7 00 00 3F CC 00 00 3E D6 00 00 40
00 00 00 40 4D 00 00 40 04 00 00 3F A9 00 00 40
82 00 00 41 0F 00 00 41 64 00 00 41 E5 00 00 42
1E 00 00 42 2C 00 00 42 80 00 00 42 4D 00 00 43
9F 00 00 43 DA 00 00 44 45 00 00 44 21 00 00 44
B7 00 00 45 22 00 00 45 E3 00 00 45 BF 00 00 46
18 00 00 47 4B 00 00 45 05 00 00 47 34 00 00 46
60 00 00 46 97 00 00 46 66 00 00 46 29 00 00 46
38 00 00 47 1D 00 00 47 42 00 00 47 18 00 00 47
13 00 00 46 52 00 00 47 48 00 00 46 F8 00 01 BE
E3 00 00 3F 56 00 00 3B 32 00 00 38 F8 00 00 37
56 00 00 36 2D 00 00 35 DA 00 00 34 6B 00 00 3E
BE 00 00 3E B5 00 00 3F 33 00 00 3F AC 00 00 3F
38 00 00 42 32 00 01 1B DC 00 01 80 50 00 01 14
06 00 00 C2 BB 00 00 96 12 00 00 6D EC 00 00 54
E6 00 00 3A AC 00 00 32 00 00 00 2F 0A 00 00 2D
F1 00 00 1B 7F 00 00 00 1C 73 74 63 6F 00 00 00
00 00 00 00 03 00 00 00 30 00 0F DD AB 00 1F 7D
9E 00 00 00 62 75 64 74 61 00 00 00 5A 6D 65 74
61 00 00 00 00 00 00 00 21 68 64 6C 72 00 00 00
00 00 00 00 00 6D 64 69 72 61 70 70 6C 00 00 00
00 00 00 00 00 00 00 00 00 2D 69 6C 73 74 00 00
00 25 A9 74 6F 6F 00 00 00 1D 64 61 74 61 00 00
00 01 00 00 00 00 4C 61 76 66 35 37 2E 32 33 2E
31 30 30Thanks a lot for any advices.
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How to ffmpeg resize 2.7k DJI Phantom Standard video to 1080p good quality ?
23 mai 2016, par augreffmpeg -i :
Duration: 00:01:59.99, start: 0.000000, bitrate: 39988 kb/s
Stream #0:0(eng): Video: h264 (High) (avc1 / 0x31637661), yuv420p(tv, bt709), 2704x1520 [SAR 1:1 DAR 169:95], 39984 kb/s, 29.97 fps, 29.97 tbr, 30k tbn, 59.94 tbc (default)
Metadata:
creation_time : 2016-05-22 11:04:26
handler_name : DJI.AVC
encoder : Dji AVC encoderI used :
ffmpeg -i DJI_0002.MOV -vf scale=1920:1080 DJI_0002FullHD.MOVBut the output quality is much worse than it should be.
How to improve the quality ?
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Using ffmpeg.exe making the computer slow in task manager it takes over 1GB of memory how can i fix it ?
29 mai 2013, par Revuen Ben DrorIn mt Form1 i have this code :
private void StartRecording_Click(object sender, EventArgs e)
{
ffmp.Start("test.avi", 25);
timer1.Enabled = true;
}ffmp is a variable of my class : Ffmpeg
In this class i add frames to a pipe and create an avi file.using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Drawing;
using System.IO.Pipes;
using System.Runtime.InteropServices;
using System.Diagnostics;
namespace ScreenVideoRecorder
{
class Ffmpeg
{
NamedPipeServerStream p;
String pipename = "mytestpipe";
byte[] b;
System.Diagnostics.Process process;
public Ffmpeg()
{
}
public void Start(string FileName, int BitmapRate)
{
p = new NamedPipeServerStream(pipename, PipeDirection.Out, 1, PipeTransmissionMode.Byte);
b = new byte[1920 * 1080 * 3]; // some buffer for the r g and b of pixels of an image of size 720p
process = new System.Diagnostics.Process();
process.StartInfo.FileName = @"D:\pipetest\pipetest\ffmpegx86\ffmpeg.exe";
process.EnableRaisingEvents = false;
process.StartInfo.WorkingDirectory = @"D:\pipetest\pipetest\ffmpegx86";
process.StartInfo.Arguments = @"-f rawvideo -pix_fmt bgr0 -video_size 1920x1080 -i \\.\pipe\mytestpipe -map 0 -c:v libx264 -r " + BitmapRate + " " + FileName;
process.Start();
process.StartInfo.UseShellExecute = false;
process.StartInfo.CreateNoWindow = false;
p.WaitForConnection();
}
public void PushFrame(Bitmap bmp)
{
int length;
// Lock the bitmap's bits.
Rectangle rect = new Rectangle(0, 0, bmp.Width, bmp.Height);
//Rectangle rect = new Rectangle(0, 0, 1280, 720);
System.Drawing.Imaging.BitmapData bmpData =
bmp.LockBits(rect, System.Drawing.Imaging.ImageLockMode.ReadOnly,
bmp.PixelFormat);
int absStride = Math.Abs(bmpData.Stride);
// Get the address of the first line.
IntPtr ptr = bmpData.Scan0;
// Declare an array to hold the bytes of the bitmap.
//length = 3 * bmp.Width * bmp.Height;
length = absStride * bmpData.Height;
byte[] rgbValues = new byte[length];
int j = bmp.Height - 1;
for (int i = 0; i < bmp.Height; i++)
{
IntPtr pointer = new IntPtr(bmpData.Scan0.ToInt32() + (bmpData.Stride * j));
System.Runtime.InteropServices.Marshal.Copy(pointer, rgbValues, absStride * (bmp.Height - i - 1), absStride);
j--;
}
p.Write(rgbValues, 0, length);
bmp.UnlockBits(bmpData);
public void Close()
{
p.Close();
}
}
}The problem is when i'm running my application in this from my visual studio 2012 pro and click the button it's openning a console window and start the processing .
I tracked over it through the task manager on ffmpeg.exe and saw that it started from 996mb and very quick jumped ot 1040mb memory usage. The cpu usage was only 16%
Once i close ended this task the ffmpeg.exe everything was back to move smooth.
When it's working and i tried to drag my Form around the screen for example it was moving slow and also with some stuttering .Closed the ffmpeg.exe and i could drag the Form around smooth and quick like in regular way as it should be.
I tried to google for it and found some others with the same problem i think but i'm not sure where is the problem and how to fix it.
I'm not sure what version of ffmpeg.exe i have i'm using now but i read in some places that it's not working better with new versions but maybe i mistake here .
My windows is 8 with 6gb of ram .
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