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Somos millones 1
21 juillet 2014, par
Mis à jour : Juin 2015
Langue : français
Type : Video
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Sur d’autres sites (5560)
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bitmap to yuv , video recorded has only green pixels
19 janvier 2016, par UserAxI am trying to convert a bitmap to yuv, and recording this yuv in the ffmpeg frame recorder...
I am getting the video output with only green pixels, though when i check the properties of this video it shows the set Frame rate and the resolution...The yuv encoding part is correct, but i feel i am making mistake somewhere else, mostly in returning the yuv bytes to recording part ( getByte(byte [] yuv ) because only there the yuv.length displayed in console is 0,, rest all methods return a big value in console ...
Kindly help...
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
directory.mkdirs();
addListenerOnButton();
play=(Button)findViewById(R.id.buttonplay);
stop=(Button)findViewById(R.id.buttonstop);
record=(Button)findViewById(R.id.buttonstart);
stop.setEnabled(false);
play.setEnabled(false);
record.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
startRecording();
getByte(new byte[]{});
}
});
stop.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
stopRecording();
}
});
play.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) throws IllegalArgumentException, SecurityException, IllegalStateException {
Intent intent = new Intent(Intent.ACTION_VIEW, Uri.parse(String.valueOf(asmileys)));
intent.setDataAndType(Uri.parse(String.valueOf(asmileys)), "video/mp4");
startActivity(intent);
Toast.makeText(getApplicationContext(), "Playing Video", Toast.LENGTH_LONG).show();
}
});
}
......//......
public void getByte(byte[] yuv) {
getNV21(640, 480, bitmap);
System.out.println(yuv.length + " ");
if (audioRecord == null || audioRecord.getRecordingState() != AudioRecord.RECORDSTATE_RECORDING) {
startTime = System.currentTimeMillis();
return;
}
if (RECORD_LENGTH > 0) {
int i = imagesIndex++ % images.length;
yuvimage = images[i];
timestamps[i] = 1000 * (System.currentTimeMillis() - startTime);
}
/* get video data */
if (yuvimage != null && recording) {
((ByteBuffer) yuvimage.image[0].position(0)).put(yuv);
if (RECORD_LENGTH <= 0) {
try {
long t = 1000 * (System.currentTimeMillis() - startTime);
if (t > recorder.getTimestamp()) {
recorder.setTimestamp(t);
}
recorder.record(yuvimage);
} catch (FFmpegFrameRecorder.Exception e) {
e.printStackTrace();
}
}
}
}
public byte [] getNV21(int inputWidth, int inputHeight, Bitmap bitmap) {
int[] argb = new int[inputWidth * inputHeight];
bitmap.getPixels(argb, 0, inputWidth, 0, 0, inputWidth, inputHeight);
byte[] yuv = new byte[inputWidth * inputHeight * 3 / 2];
encodeYUV420SP(yuv, argb, inputWidth, inputHeight);
bitmap.recycle();
System.out.println(yuv.length + " ");
return yuv;
}
void encodeYUV420SP(byte[] yuv420sp, int[] argb, int width, int height) {
final int frameSize = width * height;
int yIndex = 0;
int uIndex = frameSize;
int vIndex = frameSize;
System.out.println(yuv420sp.length + " " + frameSize);
int a, R, G, B, Y, U, V;
int index = 0;
for (int j = 0; j < height; j++) {
for (int i = 0; i < width; i++) {
a = (argb[index] & 0xff000000) >> 24; // a is not used obviously
R = (argb[index] & 0xff0000) >> 16;
G = (argb[index] & 0xff00) >> 8;
B = (argb[index] & 0xff) >> 0;
// well known RGB to YUV algorithm
Y = ((66 * R + 129 * G + 25 * B + 128) >> 8) + 16;
U = ((-38 * R - 74 * G + 112 * B + 128) >> 8) + 128;
V = ((112 * R - 94 * G - 18 * B + 128) >> 8) + 128;
// NV21 has a plane of Y and interleaved planes of VU each sampled by a factor of 2
// meaning for every 4 Y pixels there are 1 V and 1 U. Note the sampling is every other
// pixel AND every other scanline.
yuv420sp[yIndex++] = (byte) ((Y < 0) ? 0 : ((Y > 255) ? 255 : Y));
if (j % 2 == 0 && index % 2 == 0) {
yuv420sp[uIndex++] = (byte) ((U < 0) ? 0 : ((U > 255) ? 255 : U));
yuv420sp[vIndex++] = (byte) ((V < 0) ? 0 : ((V > 255) ? 255 : V));
}
index++;
}
}
}
.....//.....
public void addListenerOnButton() {
image = (ImageView) findViewById(R.id.imageView);
image.setDrawingCacheEnabled(true);
image.buildDrawingCache();
bitmap = image.getDrawingCache();
System.out.println(bitmap.getByteCount() + " " );
button = (Button) findViewById(R.id.btn1);
button.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View view){
image.setImageResource(R.drawable.image1);
}
});
......//......EDIT 1 :
I made few changes in the above code :
record.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
startRecording();
getByte();
}
});
.....//....
public void getbyte() {
byte[] yuv = getNV21(640, 480, bitmap);So now in the console ; i get same yuv length in this method as the yuv length from getNV21 method..
But now i am getting half screen Black and Half screen green(black above and green below) pixels in the recorded video...
If i add these lines to onCreate method ;
image = (ImageView) findViewById(R.id.imageView);
image.setDrawingCacheEnabled(true);
image.buildDrawingCache();
bitmap = image.getDrawingCache();I do get distorted frames( frames are 1/4th of the image displayed with mix up of colors here and there) in the video....
All i am trying to learn is the image processing and flow of Bytes[] from one method to another ; but i am still a noob.. ;
Kindly help..!
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ffmpeg "End mismatch 1" warning, jpeg2000 to avi
11 avril 2023, par jklebesTrying to convert a directory of jpeg2000 grayscale images to a video with ffmpeg, I get warnings


[0;36m[jpeg2000 @ 0x55d8fa1b68c0] [0m[0;33mEnd mismatch 1


(and lots of


Last message repeated <n> times
</n>

)


The command was


ffmpeg -y -r 10 -start_number 1 -i <path>/surface_30///img_000%01d.jp2 -vcodec msmpeg4 -vf scale=1920:-1 -q:v 8 <path>//surface_30///surface_30.avi
</path></path>

The output is


ffmpeg version 4.2.2 Copyright (c) 2000-2019 the FFmpeg developers
 built with gcc 7.3.0 (crosstool-NG 1.23.0.449-a04d0)
 configuration: --prefix=/home/jklebes001/miniconda3 --cc=/tmp/build/80754af9/ffmpeg_1587154242452/_build_env/bin/x86_64-conda_cos6-linux-gnu-cc --disable-doc --enable-avresample --enable-gmp --enable-hardcoded-tables --enable-libfreetype --enable-libvpx --enable-pthreads --enable-libopus --enable-postproc --enable-pic --enable-pthreads --enable-shared --enable-static --enable-version3 --enable-zlib --enable-libmp3lame --disable-nonfree --enable-gpl --enable-gnutls --disable-openssl --enable-libopenh264 --enable-libx264
 libavutil 56. 31.100 / 56. 31.100
 libavcodec 58. 54.100 / 58. 54.100
 libavformat 58. 29.100 / 58. 29.100
 libavdevice 58. 8.100 / 58. 8.100
 libavfilter 7. 57.100 / 7. 57.100
 libavresample 4. 0. 0 / 4. 0. 0
 libswscale 5. 5.100 / 5. 5.100
 libswresample 3. 5.100 / 3. 5.100
 libpostproc 55. 5.100 / 55. 5.100
[0;36m[jpeg2000 @ 0x55cb44144480] [0m[0;33mEnd mismatch 1

[0m Last message repeated 1 times
 Last message repeated 2 times
 Last message repeated 3 times


...


Last message repeated 73 times

Input #0, image2, from '<path>//surface_30///img_000%01d.jp2':

 Duration: 00:00:00.20, start: 0.000000, bitrate: N/A

 Stream #0:0: Video: jpeg2000, gray, 6737x4869, 25 tbr, 25 tbn, 25 tbc

Stream mapping:

 Stream #0:0 -> #0:0 (jpeg2000 (native) -> msmpeg4v3 (msmpeg4))

Press [q] to stop, [?] for help

[0;36m[jpeg2000 @ 0x55cb4418e200] [0m[0;33mEnd mismatch 1

[0m[0;36m[jpeg2000 @ 0x55cb441900c0] [0m[0;33mEnd mismatch 1
</path>

...


(about 600 lines of "end mismatch" and "last message repeated" cut)


...


[0m[0;36m[jpeg2000 @ 0x55cb4418e8c0] [0m[0;33mEnd mismatch 1

[0mOutput #0, avi, to '<path>/surface_30///surface_30.avi':

 Metadata:

 ISFT : Lavf58.29.100

 Stream #0:0: Video: msmpeg4v3 (msmpeg4) (MP43 / 0x3334504D), yuv420p, 1920x1388, q=2-31, 200 kb/s, 10 fps, 10 tbn, 10 tbc

 Metadata:

 encoder : Lavc58.54.100 msmpeg4

 Side data:

 cpb: bitrate max/min/avg: 0/0/200000 buffer size: 0 vbv_delay: -1

frame= 2 fps=0.8 q=8.0 size= 6kB time=00:00:00.20 bitrate= 227.1kbits/s speed=0.0844x 
frame= 5 fps=1.7 q=8.0 size= 6kB time=00:00:00.50 bitrate= 90.8kbits/s speed=0.172x 
frame= 5 fps=1.7 q=8.0 Lsize= 213kB time=00:00:00.50 bitrate=3494.7kbits/s speed=0.172x 
video:208kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 2.732246%
</path>

What is the meaning of characters like [0 ;33m here ?


I thought it might have something to do with bit depth and color format. Setting
-pix_fmt grayhad no effect, and indeed the format of the jp2 images is already detected as 8-bit gray.

The output .avi exists and seems fine.


The line was previously used on jpeg files and works fine on jpeg. With jpeg, the output has the line


Input #0, image2, from '<path>/surface_30///img_000%01d.jpeg':

 Duration: 00:00:00.16, start: 0.000000, bitrate: N/A

 Stream #0:0: Video: mjpeg (Baseline), gray(bt470bg/unknown/unknown), 6737x4869 [SAR 1:1 DAR 6737:4869], 25 tbr, 25 tbn, 25 tbc

Stream mapping:

 Stream #0:0 -> #0:0 (mjpeg (native) -> msmpeg4v3 (msmpeg4))

Press [q] to stop, [?] for help

Output #0, avi, to '<path>/surface_30///surface_30.avi':

 Metadata:

 ISFT : Lavf58.29.100

 Stream #0:0: Video: msmpeg4v3 (msmpeg4) (MP43 / 0x3334504D), yuv420p, 6737x4869 [SAR 1:1 DAR 6737:4869], q=2-31, 200 kb/s, 10 fps, 10 tbn, 10 tbc

 Metadata:

 encoder : Lavc58.54.100 msmpeg4

 Side data:

 cpb: bitrate max/min/avg: 0/0/200000 buffer size: 0 vbv_delay: -1

frame= 2 fps=0.0 q=8.0 size= 6662kB time=00:00:00.20 bitrate=272859.9kbits/s speed=0.334x 
frame= 3 fps=2.2 q=10.0 size= 10502kB time=00:00:00.30 bitrate=286764.2kbits/s speed=0.22x 
frame= 4 fps=1.9 q=12.3 size= 13574kB time=00:00:00.40 bitrate=277987.7kbits/s speed=0.19x 
frame= 4 fps=1.4 q=12.3 size= 13574kB time=00:00:00.40 bitrate=277987.7kbits/s speed=0.145x 
frame= 4 fps=1.4 q=12.3 Lsize= 13657kB time=00:00:00.40 bitrate=279702.3kbits/s speed=0.145x 
video:13652kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 0.041926%
</path></path>

detecting mjpeg format and similar, but more detailed format
gray(bt470bg/unknown/unknown), 6737x4869 [SAR 1:1 DAR 6737:4869].

What is the difference when switching input to jp2 ?


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Is there a way to crop a video given a videoURL in node js ?
30 mars 2021, par RadespyI’m building an electron-react app and need to crop
[x, y, width, height]a video in the main process.

The video URL and buffer have been generated in a react rendering component using mediaStream / mediaRecorder and a URL / buffer generated in the render process using
URL.createObjectURL.

I need to crop the video buffer directly (i.e. select a region of interest within the video) without having to download a file.


I would then like to create a buffer from the cropped video to save in MongoDB as a base64 encoded string.


I’ve looked at
fluent-ffmpegbut this doesn’t seem to work with a URL or buffer and requires a path to a downloaded video file.

Does anyone know of a way to do this ?


Many thanks


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