Use CharacterEncodingDetector in metadataretriever
instead of media scanner. This way the java MediaMetadataRetriever API
will give the same result as the media scanner.
Also apply some tweaks to the encoding detector to improve handling of
ISO-8859-1 tags.
Bug: 16302581, 17205395
Change-Id: I1682a7a6a8bf04cffaa455044ba72dd7fd152d49
diff --git a/media/libmedia/CharacterEncodingDetector.cpp b/media/libmedia/CharacterEncodingDetector.cpp
index 7d1ddfd..41994dc 100644
--- a/media/libmedia/CharacterEncodingDetector.cpp
+++ b/media/libmedia/CharacterEncodingDetector.cpp
@@ -18,7 +18,7 @@
#define LOG_TAG "CharacterEncodingDector"
#include <utils/Log.h>
-#include "CharacterEncodingDetector.h"
+#include <CharacterEncodingDetector.h>
#include "CharacterEncodingDetectorTables.h"
#include "utils/Vector.h"
@@ -118,10 +118,12 @@
int32_t matches;
const UCharsetMatch** ucma = ucsdet_detectAll(csd, &matches, &status);
bool goodmatch = true;
+ int highest = 0;
const UCharsetMatch* bestCombinedMatch = getPreferred(buf, strlen(buf),
- ucma, matches, &goodmatch);
+ ucma, matches, &goodmatch, &highest);
- if (!goodmatch && strlen(buf) < 20) {
+ ALOGV("goodmatch: %s, highest: %d", goodmatch ? "true" : "false", highest);
+ if (!goodmatch && (highest < 15 || strlen(buf) < 20)) {
ALOGV("not a good match, trying with more data");
// This string might be too short for ICU to do anything useful with.
// (real world example: "Björk" in ISO-8859-1 might be detected as GB18030, because
@@ -146,9 +148,10 @@
ucsdet_setText(csd, buf, strlen(buf), &status);
ucma = ucsdet_detectAll(csd, &matches, &status);
bestCombinedMatch = getPreferred(buf, strlen(buf),
- ucma, matches, &goodmatch);
- if (!goodmatch) {
+ ucma, matches, &goodmatch, &highest);
+ if (!goodmatch && highest <= 15) {
ALOGV("still not a good match after adding printable tags");
+ bestCombinedMatch = NULL;
}
} else {
ALOGV("no printable tags to add");
@@ -157,6 +160,8 @@
if (bestCombinedMatch != NULL) {
combinedenc = ucsdet_getName(bestCombinedMatch, &status);
+ } else {
+ combinedenc = "ISO-8859-1";
}
}
@@ -199,10 +204,17 @@
if (strcmp(enc,"UTF-8") != 0) {
// only convert if the source encoding isn't already UTF-8
ALOGV("@@@ using converter %s for %s", enc, mNames.getEntry(i));
+ status = U_ZERO_ERROR;
UConverter *conv = ucnv_open(enc, &status);
if (U_FAILURE(status)) {
- ALOGE("could not create UConverter for %s", enc);
- continue;
+ ALOGW("could not create UConverter for %s (%d), falling back to ISO-8859-1",
+ enc, status);
+ status = U_ZERO_ERROR;
+ conv = ucnv_open("ISO-8859-1", &status);
+ if (U_FAILURE(status)) {
+ ALOGW("could not create UConverter for ISO-8859-1 either");
+ continue;
+ }
}
// convert from native encoding to UTF-8
@@ -224,7 +236,16 @@
} else {
// zero terminate
*target = 0;
- mValues.setEntry(i, buffer);
+ // strip trailing spaces
+ while (--target > buffer && *target == ' ') {
+ *target = 0;
+ }
+ // skip leading spaces
+ char *start = buffer;
+ while (*start == ' ') {
+ start++;
+ }
+ mValues.setEntry(i, start);
}
delete[] buffer;
@@ -261,7 +282,7 @@
const UCharsetMatch *CharacterEncodingDetector::getPreferred(
const char *input, size_t len,
const UCharsetMatch** ucma, size_t nummatches,
- bool *goodmatch) {
+ bool *goodmatch, int *highestmatch) {
*goodmatch = false;
Vector<const UCharsetMatch*> matches;
@@ -316,11 +337,17 @@
}
ALOGV("%zu: %s %d", i, encname, confidence);
+ status = U_ZERO_ERROR;
UConverter *conv = ucnv_open(encname, &status);
+ int demerit = 0;
+ if (U_FAILURE(status)) {
+ ALOGV("failed to open %s: %d", encname, status);
+ confidence = 0;
+ demerit += 1000;
+ }
const char *source = input;
const char *sourceLimit = input + len;
status = U_ZERO_ERROR;
- int demerit = 0;
int frequentchars = 0;
int totalchars = 0;
while (true) {
@@ -337,7 +364,8 @@
if (c < 0x20 || (c >= 0x7f && c <= 0x009f)) {
ALOGV("control character %x", c);
demerit += 100;
- } else if ((c >= 0xa0 && c <= 0xbe) // symbols, superscripts
+ } else if ((c == 0xa0) // no-break space
+ || (c >= 0xa2 && c <= 0xbe) // symbols, superscripts
|| (c == 0xd7) || (c == 0xf7) // multiplication and division signs
|| (c >= 0x2000 && c <= 0x209f)) { // punctuation, superscripts
ALOGV("unlikely character %x", c);
@@ -408,10 +436,14 @@
} else {
ALOGV("runner up: '%s' w/ %d confidence",
ucsdet_getName(matches[runnerupidx], &status), runnerup);
+ if (runnerup < 0) {
+ runnerup = 0;
+ }
if ((highest - runnerup) > 15) {
*goodmatch = true;
}
}
+ *highestmatch = highest;
return matches[highestidx];
}