org.monte.media.jpeg.JFIFInputStream Maven / Gradle / Ivy
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package org.monte.media.jpeg;
import java.io.*;
import java.util.*;
public class JFIFInputStream extends FilterInputStream {
private final HashSet standaloneMarkers = new HashSet();
private final HashSet doubleSegMarkers = new HashSet();
public static class Segment {
public final int marker;
public final long offset;
public final int length;
public Segment(int marker, long offset, int length) {
this.marker = marker;
this.offset = offset;
this.length = length;
}
public boolean isEntropyCoded() {
return length == -1;
}
@Override
public String toString() {
return "Segment marker=0x" + Integer.toHexString(marker) + " offset=" + offset + "=0x" + Long.toHexString(offset);
}
}
private Segment segment;
private boolean markerFound;
private int marker = JUNK_MARKER;
private long offset = 0;
private boolean isStuffed0xff = false;
public final static int JUNK_MARKER = -1;
public final static int SOI_MARKER = 0xffd8;
public final static int EOI_MARKER = 0xffd9;
public final static int TEM_MARKER = 0xff01;
public final static int SOS_MARKER = 0xffda;
public final static int APP1_MARKER = 0xffe1;
public final static int APP2_MARKER = 0xffe2;
public final static int JPG0_MARKER = 0xfff0;
public final static int JPG1_MARKER = 0xfff1;
public final static int JPG2_MARKER = 0xfff2;
public final static int JPG3_MARKER = 0xfff3;
public final static int JPG4_MARKER = 0xfff4;
public final static int JPG5_MARKER = 0xfff5;
public final static int JPG6_MARKER = 0xfff6;
public final static int JPG7_MARKER = 0xfff7;
public final static int JPG8_MARKER = 0xfff8;
public final static int JPG9_MARKER = 0xfff9;
public final static int JPGA_MARKER = 0xfffA;
public final static int JPGB_MARKER = 0xfffB;
public final static int JPGC_MARKER = 0xfffC;
public final static int JPGD_MARKER = 0xfffD;
public final static int SOF0_MARKER = 0xffc0;
public final static int SOF1_MARKER = 0xffc1;
public final static int SOF2_MARKER = 0xffc2;
public final static int SOF3_MARKER = 0xffc3;
public final static int SOF5_MARKER = 0xffc5;
public final static int SOF6_MARKER = 0xffc6;
public final static int SOF7_MARKER = 0xffc7;
public final static int SOF9_MARKER = 0xffc9;
public final static int SOFA_MARKER = 0xffcA;
public final static int SOFB_MARKER = 0xffcB;
public final static int SOFD_MARKER = 0xffcD;
public final static int SOFE_MARKER = 0xffcE;
public final static int SOFF_MARKER = 0xffcF;
public final static int RST0_MARKER = 0xffd0;
public final static int RST1_MARKER = 0xffd1;
public final static int RST2_MARKER = 0xffd2;
public final static int RST3_MARKER = 0xffd3;
public final static int RST4_MARKER = 0xffd4;
public final static int RST5_MARKER = 0xffd5;
public final static int RST6_MARKER = 0xffd6;
public final static int RST7_MARKER = 0xffd7;
public JFIFInputStream(File f) throws IOException {
this(new BufferedInputStream(new FileInputStream(f)));
}
public JFIFInputStream(InputStream in) {
super(in);
for (int i = RST0_MARKER; i <= RST7_MARKER; i++) {
standaloneMarkers.add(i);
}
standaloneMarkers.add(SOI_MARKER);
standaloneMarkers.add(EOI_MARKER);
standaloneMarkers.add(TEM_MARKER);
standaloneMarkers.add(JPG0_MARKER);
standaloneMarkers.add(JPG1_MARKER);
standaloneMarkers.add(JPG2_MARKER);
standaloneMarkers.add(JPG3_MARKER);
standaloneMarkers.add(JPG4_MARKER);
standaloneMarkers.add(JPG5_MARKER);
standaloneMarkers.add(JPG6_MARKER);
standaloneMarkers.add(JPG7_MARKER);
standaloneMarkers.add(JPG8_MARKER);
standaloneMarkers.add(JPG9_MARKER);
standaloneMarkers.add(JPGA_MARKER);
standaloneMarkers.add(JPGB_MARKER);
standaloneMarkers.add(JPGC_MARKER);
standaloneMarkers.add(JPGD_MARKER);
standaloneMarkers.add(0xffff);
doubleSegMarkers.add(SOS_MARKER);
segment = new Segment(-1, 0, -1);
}
public Segment getSegment() throws IOException {
return segment;
}
public Segment getNextSegment() throws IOException {
if (!segment.isEntropyCoded()) {
markerFound = false;
do {
long skipped = in.skip(segment.length - offset + segment.offset);
if (skipped == -1) {
segment = new Segment(0, offset, -1);
return null;
}
offset += skipped;
} while (offset < segment.length + segment.offset);
if (doubleSegMarkers.contains(segment.marker)) {
segment = new Segment(0, offset, -1);
return segment;
}
}
while (!markerFound) {
while (true) {
int b;
if (isStuffed0xff) {
b = 0xff;
isStuffed0xff = false;
} else {
b = read0();
}
if (b == -1) {
return null;
}
if (b == 0xff) {
markerFound = true;
break;
}
}
int b = read0();
if (b == -1) {
return null;
}
if (b == 0x00) {
markerFound = false;
} else if (b == 0xff) {
isStuffed0xff = true;
markerFound = false;
} else {
marker = 0xff00 | b;
}
}
markerFound = false;
if (standaloneMarkers.contains(marker)) {
segment = new Segment(0xff00 | marker, offset, -1);
} else {
int length = (read0() << 8) | read0();
if (length < 2) {
throw new IOException("JFIFInputStream found illegal segment length " + length + " after marker " + Integer.toHexString(marker) + " at offset " + offset + ".");
}
segment = new Segment(0xff00 | marker, offset, length - 2);
}
return segment;
}
public long getStreamPosition() {
return offset;
}
private int read0() throws IOException {
int b = in.read();
if (b != -1) {
offset++;
}
return b;
}
@Override
public int read() throws IOException {
if (markerFound) {
return -1;
}
int b;
if (isStuffed0xff) {
isStuffed0xff = false;
b = 0xff;
} else {
b = read0();
}
if (segment.isEntropyCoded()) {
if (b == 0xff) {
b = read0();
if (b == 0x00) {
return 0xff;
} else if (b == 0xff) {
isStuffed0xff = true;
return 0xff;
}
markerFound = true;
marker = 0xff00 | b;
return -1;
}
}
return b;
}
@Override
public int read(byte b[], int off, int len) throws IOException {
if (markerFound) {
return -1;
}
int count = 0;
if (segment.isEntropyCoded()) {
for (; count < len; count++) {
int data = read();
if (data == -1) {
if (count==0) return -1;
break;
}
b[off + count] = (byte) data;
}
} else {
long available = segment.length - offset + segment.offset;
if (available <= 0) {
return -1;
}
if (available < len) {
len = (int) available;
}
count = in.read(b, off, len);
if (count != -1) {
offset += count;
}
}
return count;
}
public final void skipFully(long n) throws IOException {
long total = 0;
long cur = 0;
while ((total < n) && ((cur = (int) in.skip(n - total)) > 0)) {
total += cur;
}
offset+=total;
if (total < n) {
throw new EOFException();
}
}
@Override
public long skip(long n) throws IOException {
if (markerFound) {
return -1;
}
long count = 0;
if (segment.isEntropyCoded()) {
for (; count < n; count++) {
int data = read();
if (data == -1) {
break;
}
}
} else {
long available = segment.length - offset + segment.offset;
if (available < n) {
n = (int) available;
}
count = in.skip(n);
if (count != -1) {
offset += count;
}
}
return count;
}
@Override
public synchronized void mark(int readlimit) {
}
@Override
public synchronized void reset() throws IOException {
throw new IOException("Reset not supported");
}
@Override
public boolean markSupported() {
return false;
}
}
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