MediaCodecBufferedOutput index is negative for android MediaCodec - java

Following is a code snippet which is supposed to read all images from image folder and encode them to a h.262 video and store in the sdcard. I followed the android documentation (get buffer, fill buffer, queue buffer for encoding, dequeue output buffer and then write to file). Problem is when I dequeue output buffer I get negative index whereas its supposed to return the index of output data. The output file is 0 Bytes and nothing is written into it.
I am pretty much very new in mediaCodec. Any suggestion would be appreciated.
MediaCodec mediaCodec=null;
byte[] input = new byte[2000];
BufferedOutputStream outputStream = null;
try {
//TODO
//adjust parameters by consulting with hari sir
mediaCodec = MediaCodec.createEncoderByType("video/avc");
MediaFormat mediaFormat = MediaFormat.createVideoFormat("video/avc", 320, 240);
mediaFormat.setInteger(MediaFormat.KEY_BIT_RATE, 700000);
mediaFormat.setInteger(MediaFormat.KEY_FRAME_RATE, 10);
//not all phones support given color format, if color format is not supported app will crash with mediaCodec exception
mediaFormat.setInteger(MediaFormat.KEY_COLOR_FORMAT, MediaCodecInfo.CodecCapabilities.COLOR_FormatYUV420Planar);
mediaFormat.setInteger(MediaFormat.KEY_I_FRAME_INTERVAL, 5);
mediaCodec.configure(mediaFormat, null, null, MediaCodec.CONFIGURE_FLAG_ENCODE);
mediaCodec.start();
//after the mediaCodec is started we don't have ownership of input or output buffers
Log.i("Codecinfo",""+mediaCodec.getCodecInfo());
Log.i("Codecname",""+mediaCodec.getName());
}
catch (Exception e)
{
Log.e("ExceptionMediaCodec","Some exception in media codec");
}
//reached here
System.out.println("mediacodec info="+mediaCodec.getCodecInfo());
try {
File ff = new File(Environment.getExternalStorageDirectory(), "Download/video_encoded.264");
if (!ff.exists()) ff.createNewFile();
System.out.println("H.264 output file initialized");
outputStream = new BufferedOutputStream(new FileOutputStream(ff));
Log.i("H264 avc Encoder", "outputStream initialized");
} catch (Exception e){
e.printStackTrace();
}
String path = Environment.getExternalStorageDirectory().toString()+"/images";
File f = new File(path);
Log.i("ExternalFileInfo",path.toString());
//read image files onto an array
File[] files = f.listFiles();
System.out.println(files.getClass().getName());
int NUM_IMAGES = files.length;
String[] images = new String[NUM_IMAGES];
for (int i=0;i<NUM_IMAGES;i++)
images[i]=files[i].getName();
for (String eachimage: images) {
System.out.println(eachimage);
byte[] eachByte = eachimage.getBytes();
input = eachByte; //demo
System.out.println("input byte initialized"+input.toString());
try {
System.out.println("Following is the content of byte array input");
System.out.write(input);
}catch (Exception e)
{
e.printStackTrace();
}
}
//reached here
System.out.println("image byte size="+input.length);
//all images converted to bytearray
ByteBuffer[] outputBuffers = mediaCodec.getOutputBuffers();
//System.out.println("inputBuffers="+(inputBuffers));
//System.out.println("outputBuffers="+(outputBuffers));
//reached here
//returns the index of input buffer to be filled for encoding
int inputBufferIndex = mediaCodec.dequeueInputBuffer(-1); //-1 => wait indefinitely
System.out.println("inputBufferedIndex="+inputBufferIndex); //0
if (inputBufferIndex >= 0) {
ByteBuffer[] inputBuffers = mediaCodec.getInputBuffers();
ByteBuffer inputBuffer = inputBuffers[inputBufferIndex];
inputBuffer.clear();
System.out.println("input byte placed in input buffer");
inputBuffer.put(input);
System.out.println("inputBuffer after filling up" + inputBuffer);
mediaCodec.queueInputBuffer(inputBufferIndex, 0, input.length, System.nanoTime(), 0); //send each request with different timestamp
System.out.println("mediacodec input queued");
}
MediaCodec.BufferInfo bufferInfo = new MediaCodec.BufferInfo();
System.out.println("buffer info="+bufferInfo);
int outputBufferIndex = mediaCodec.dequeueOutputBuffer(bufferInfo, -1); //-ve value for indefinite waiting
//reached here
System.out.println("buffer info meta data=" + bufferInfo);
System.out.println("outputBufferedIndex=" + outputBufferIndex);
try {
while (outputBufferIndex >= 0) {
ByteBuffer outputBuffer = outputBuffers[outputBufferIndex];
byte[] outData = new byte[bufferInfo.size];
outputBuffer.get(outData);
outputStream.write(outData, 0, outData.length);
outputStream.flush();
Log.i("AvcEncoder", outData.length + " bytes written");
mediaCodec.releaseOutputBuffer(outputBufferIndex, false);
outputBufferIndex = mediaCodec.dequeueOutputBuffer(bufferInfo, -1);
}
} catch (Throwable t) {
t.printStackTrace();
}
try {
mediaCodec.stop();
mediaCodec.release();
outputStream.flush();
outputStream.close();
} catch (Exception e){
e.printStackTrace();
}
System.out.println("Mediacodec="+mediaCodec);

Please see the documentation for the MediaCodec.dequeueOutputBuffer() method, which says:
Returns the index of an output buffer that has been successfully decoded or one of the INFO_* constants.
The negative values are the INFO_* constants, which may be one of the following:
INFO_OUTPUT_BUFFERS_CHANGED
INFO_OUTPUT_FORMAT_CHANGED
INFO_TRY_AGAIN_LATER
The last one is not too probable because you're waiting indefinitely though.
Additionally: You can't always rely on waiting for one output buffer after you've given one single buffer as input. You need to feed input buffers as long as the encoder has got free input buffers, and consume whatever output buffers it gives you.
The last few output buffers might be output only once you signal that you won't be submitting any more input buffers, by setting the flag BUFFER_FLAG_END_OF_STREAM.

Related

why is BufferedInputStream reading max 2048 bytes at a time?

I'm trying to read a file from network using HttpUrlConnection in an AsyncTask in my Android Application.
While i noticed one thing that the file download worked a little slower than it should have, as the network speed i was using was faster.
So i checked and found out that the BufferedInputStream object reads only 2048 bytes max at a time. No what buffer size I set. Even internal default buffer size for BufferedInputStream is 8192 bytes.
I'm adding my code here for reference.
private class DownloadFileTask extends AsyncTask<String, Integer, String> {
#Override
protected String doInBackground(String... params) {
HttpURLConnection connection = null;
BufferedInputStream input = null;
OutputStream output = null;
int lengthOfFile;
int totalBytesDownloaded = 0;
int count;
final int bufferSize = 8 * 1024; // 8KB
try {
// Create the URL
URL url = new URL(params[0]);
// Open connection
connection = (HttpURLConnection) url.openConnection();
// Get the file length
lengthOfFile = connection.getContentLength();
// Input stream to read file - with bufferSize buffer
input = new BufferedInputStream(connection.getInputStream(), bufferSize);
if (isCancelled()) {
return null;
}
// Output stream to write file
File parentFile = TestUtil.getStorageDir(getApplicationContext(),Constants.EXTRA_DIRECTORY_NAME_TEST_MEDIA);
File file = new File(parentFile.getAbsolutePath() + "/" + "zipFile");
if (!file.exists()) {
file.getParentFile().mkdirs();
}
// Create the file o/p stream
output = new FileOutputStream(file.getAbsolutePath());
// Create the buffer o/p stream for performance
BufferedOutputStream bos = new BufferedOutputStream(output, bufferSize);
// Buffer
byte data[] = new byte[bufferSize];
while ((count = input.read(data, 0, bufferSize)) != -1 && !isCancelled()) {
// Increase the total bytes downloaded
totalBytesDownloaded += count;
Log.d("DEBUG_LOG","total bytes read : " + count + " buffer size : " + data.length);
// Write the data to the o/p buffer
bos.write(data, 0, count);
}
// Publish update again since the loop may have skipped the last publish update
publishProgress(totalBytesDownloaded, lengthOfFile);
// Flush the o/p stream
output.flush();
return file.getAbsolutePath();
} catch (SocketException | SocketTimeoutException e) {
handler.sendEmptyMessage(Constants.CASE_INTERNET_FAILURE);
Log.e("DEBUG_LOG", e);
} catch (IOException e) {
Log.e("DEBUG_LOG","Error: " + e.getMessage());
} finally {
// closing streams
if (output != null) {
try {
output.close();
} catch (IOException e) {
AMLog.e(e);
}
}
if (input != null) {
try {
input.close();
} catch (IOException e) {
AMLog.e(e);
}
}
if (connection != null) {
connection.disconnect();
}
}
return null;
}
#Override
protected void onProgressUpdate(Integer... values) {
int percentage = (values[0] * 100) / values[1] ;
textDownloadSizeMb.setText(String.format(getString(R.string.label_download_mb), String.valueOf(values[0]), String.valueOf(values[1])));
textDownloadPercent.setText(String.format(Locale.getDefault(), "%s%s", percentage, " %"));
progressBar.setMax(values[1]);
progressBar.setProgress(values[0]);
}
#Override
protected void onPostExecute(String value) {
}
}
Here is a part of log that shows the data read was never greater than 2048 bytes whereas the buffer size was 8192 bytes.
total bytes read : 1748 buffer size : 8192
total bytes read : 2048 buffer size : 8192
total bytes read : 2048 buffer size : 8192
total bytes read : 2048 buffer size : 8192
total bytes read : 1988 buffer size : 8192
I've tried multiple buffer sizes greater than 2048 but nothing seems to change the reading rate.
What's the reason behind this? Can i change it to get data in specified buffer size?
Because that's all that is ready to be read at any one time, due to the way it is being sent. Nothing you can do about that at this end, except maybe read less often ;-) There's no particular reason to want 8192 bytes at a time: in a correctly written read loop you shouldn't care whether it's one byte or a megabyte, or whatever your buffer size is. The contract of read() is merely that it transfers 'at least one byte', unless an exception or end of stream occurs.

using write() method, the file gets too big

I try to write to a file, the data that I receive from a socket , I store the data in an array but when I write them, the file gets too big ...
I think it is caused by using a big array , as i don't know the length of the data stream...
But checking the method write it is stated that write(byte[] b) Writes b.length bytes from the specified byte array to this file output stream,
the write() method reads the length of the array but the length is 2000...
How can i know the length of the data that will be written?
...
byte[] Rbuffer = new byte[2000];
dis = new DataInputStream(socket.getInputStream());
dis.read(Rbuffer);
writeSDCard.writeToSDFile(Rbuffer);
...
void writeToSDFile(byte[] inputMsg){
File root = android.os.Environment.getExternalStorageDirectory();
File dir = new File (root.getAbsolutePath() + "/download");
if (!(dir.exists())) {
dir.mkdirs();
}
Log.d("WriteSDCard", "Start writing");
File file = new File(dir, "myData.txt");
try {
FileOutputStream f = new FileOutputStream(file, true);
f.write(inputMsg);
f.close();
} catch (FileNotFoundException e) {
e.printStackTrace();
Log.i(TAG, "******* File not found. Did you" +
" add a WRITE_EXTERNAL_STORAGE permission to the manifest?");
} catch (IOException e) {
e.printStackTrace();
}
}
read() returns the number of bytes that were read, or -1. You are ignoring both possibilities, and assuming that it filled the buffer. All you have to do is store the result in a variable, check for -1, and otherwise pass it to the write() method.
Actually you should pass the input stream to your method, and use a loop after creating the file:
int count;
byte[] buffer = new byte[8192];
while ((count = in.read(buffer)) > 0)
{
out.write(buffer, 0, count);
}
Your statement in a now-deleted comment that a new input stream is created per packet is not correct.

From FileInputStream to BufferedInputStream conversion

we were given a few exercises in lab and one of these is to convert the file transferring method from FileInputStream to BufferedInputStream. It's a client sending a GET request to a web server, which sends the file requested.
I came up with a simple solution, and I just wanted to check if it's correct.
Original code:
try {
FileInputStream fis = new FileInputStream(req);
// req, String containing file name
byte[] data = new byte [fis.available()];
fis.read(data);
out.write(data); // OutputStream out = socket.getOutputStream();
} catch (FileNotFoundException e){
new PrintStream(out).println("404 Not Found");
}
My try:
try {
BufferedInputStream bis = new BufferedInputStream (new FileInputStream(req));
byte[] data = new byte[4];
while(bis.read(data) > -1) {
out.write(data);
data = new byte[4];
}
} catch (FileNotFoundException e){
new PrintStream(out).println("404 Not Found");
}
The file is a web page named index.html, which contains a simple html page.
I have to reallocate the array every time, because at the last execution of the while loop, if the file isn't a multiple of 4 in size, the data array will contain characters from the previous execution, which are shown in the browser.
I chose 4 as data size for debugging purposes.
Output is correct.
Is this a good solution or can I do better?
There's no need to re-create the byte array each time - just overwrite it. More importantly though, you have a conceptual mistake inside your loop. Each iteration just writes the array to the stream assuming it's all valid. If you examine BufferedInputStream#read's documentation you'll see it may not read enough data to fill the entire array, and will return the number of bytes it actually read. You should use this number to limit the amount of bytes you're writing:
while((int len = bis.read(data)) > -1) {
out.write(data, 0, len);
}
I suggest you close off your file once you are done. The BufferedInputStream uses an 8 KB buffer by default which you are reducing to a smaller buffer. A simpler solution is to copy 8 KB at a time and not use the added buffer
try (InputStream in = new FileInputStream(req)) {
byte[] data = new byte[8 << 10];
for (int len; (len = bis.read(data)) > -1; )
out.write(data, 0, len);
} catch (IOException e) {
out.write("404 Not Found\n".getBytes());
}

Why does getResourceAsStream() and reading file with FileInputStream return arrays of different length?

I want to read files as byte arrays and realised that amount of read bytes varies depending on the used method. Here the relevant code:
public byte[] readResource() {
try (InputStream is = getClass().getClassLoader().getResourceAsStream(FILE_NAME)) {
int available = is.available();
byte[] result = new byte[available];
is.read(result, 0, available);
return result;
} catch (Exception e) {
log.error("Failed to load resource '{}'", FILE_NAME, e);
}
return new byte[0];
}
public byte[] readFile() {
File file = new File(FILE_PATH + FILE_NAME);
try (InputStream is = new FileInputStream(file)) {
int available = is.available();
byte[] result = new byte[available];
is.read(result, 0, available);
return result;
} catch (Exception e) {
log.error("Failed to load file '{}'", FILE_NAME, e);
}
return new byte[0];
}
Calling File.length() and reading with the FileInputStream returns the correct length of 21566 bytes for the given test file, though reading the file as a resources returns 21622 bytes.
Does anyone know why I get different results and how to fix it so that readResource() returns the correct result?
Why does getResourceAsStream() and reading file with FileInputStream return arrays of different length?
Because you're misusing the available() method in a way that is specifically warned against in the Javadoc:
"It is never correct to use the return value of this method to allocate a buffer intended to hold all data in this stream."
and
Does anyone know why I get different results and how to fix it so that readResource() returns the correct result?
Read in a loop until end of stream.
According to the the API docs of InputStream, InputStream.available() does not return the size of the resource - it returns
an estimate of the number of bytes that can be read (or skipped over) from this input stream without blocking
To get the size of a resource from a stream, you need to fully read the stream, and count the bytes read.
To read the stream and return the contents as a byte array, you could do something like this:
try ( InputStream is = getClass().getClassLoader().getResourceAsStream(FILE_NAME);
ByteArrayOutputStream bos = new ByteArrayOutputStream()) {
byte[] buffer = new byte[4096];
int bytesRead = 0;
while ((bytesRead = is.read(buffer)) != -1) {
bos.write(buffer, 0, bytesRead);
}
return bos.toByteArray();
}

Error while sending large files through socket

I'm trying to send large files via socket. The program works fine for small files (such as html pages or pdf), but when i send files over 3/4 mb the output is always corrupted (viewing it with a text editor i noticed that the last few lines are always missing).
Here's the code of the server:
BufferedInputStream in = null;
FileOutputStream fout = null;
try {
server = new ServerSocket(port);
sock = server.accept();
in = new BufferedInputStream(sock.getInputStream());
setPerc(0);
received = 0;
int incByte = -1;
fout = new FileOutputStream(path+name, true);
long size = length;
do{
int buffSize;
if(size >= 4096){
buffSize = 4096;
}else{
buffSize = 1;
}
byte[] o = new byte[buffSize];
incByte = in.read(o, 0, buffSize);
fout.write(o);
received+=buffSize;
setPerc(calcPerc(received, length));
size -= buffSize;
//d("BYTE LETTI => "+incByte);
}while(size > 0);
server.close();
} catch (IOException e) {
e("Errore nella ricezione file: "+e);
}finally{
try {
fout.flush();
fout.close();
in.close();
} catch (IOException e) {
e("ERRORE INCOMINGFILE");
}
}
pr.release(port);
And here's the code of the client:
FileInputStream fin = null;
BufferedOutputStream out = null;
try {
sock = new Socket(host, port);
fin = new FileInputStream(file);
out = new BufferedOutputStream(sock.getOutputStream());
long size = file.length();
int read = -1;
do{
int buffSize = 0;
if(size >= 4096){
buffSize = 4096;
}else{
buffSize = (int)size;
}
byte[] o = new byte[buffSize];
for(int i = 0; i<o.length;i++){
o[i] = (byte)0;
}
read = fin.read(o, 0, buffSize);
out.write(o);
size -= buffSize;
//d("BYTE LETTI DAL FILE => "+read);
}while(size > 0);
} catch (UnknownHostException e) {
} catch (IOException e) {
d("ERRORE NELL'INVIO DEL FILE: "+e);
e.printStackTrace();
}finally{
try {
out.flush();
out.close();
fin.close();
} catch (IOException e) {
d("Errore nella chiusura dei socket invio");
}
}
i think it's something related with the buffer size, but i can't figure out what's wrong here.
This is incorrect:
byte[] o = new byte[buffSize];
incByte = in.read(o, 0, buffSize);
fout.write(o);
You are reading up to buffSize bytes and then writing exactly buffSize bytes.
You are doing the same thing at the other end as well.
You may be able to get away with this when reading from a file1, but when you read from a socket then a read is liable to give you a partially filled buffer, especially if the writing end can't always keep ahead of the reading end 'cos you are hammering the network with a large transfer.
The right way to do it is:
incByte = in.read(o, 0, buffSize);
fout.write(o, 0, incByte);
1 - It has been observed that when you read from a local file, a read call will typically give you all of the bytes that you requested (subject to the file size, etc). So, if you set buffSize to the length of the file, this code would probably work when reading from a local file. But doing this is a bad idea, because you are relying behaviour that is not guaranteed by either Java or a typical operating system.
You might have a problem e.g. here.
read = fin.read(o, 0, buffSize);
out.write(o);
Here read gives you the count of bytes you've actually just read.
On the next line you should write out only as many bytes as you've read.
In other words, you cannot expect the size of the file
you're reading to be multiple of your buffer size.
Review your server code too for the same issue.
The correct way to copy streams in Java is as follows:
while ((count = in.read(buffer)) > 0)
{
out.write(buffer, 0, count);
}
where count is an int, and buffer is a byte[] array of length > 0, typically 8k. You don't need to allocate byte arrays inside the loop, and you don't need a byte array of a specific size. Specifically, it's a complete waste of space to allocate a buffer as large as the file; it only works up to files of Integer.MAX_VALUE bytes, and it doesn't scale.
You do need to save the count returned by 'read()' and use it in the 'write()' method as shown above.

Categories