blob: 4a0c35c6784148ec29e91aa3fa863855df39c941 [file] [log] [blame]
/*
* Copyright (C) 2009 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
//#define LOG_NDEBUG 0
#define LOG_TAG "ESDS"
#include <utils/Log.h>
#include "include/ESDS.h"
#include <string.h>
namespace android {
ESDS::ESDS(const void *data, size_t size)
: mData(new uint8_t[size]),
mSize(size),
mInitCheck(NO_INIT),
mDecoderSpecificOffset(0),
mDecoderSpecificLength(0),
mObjectTypeIndication(0) {
memcpy(mData, data, size);
mInitCheck = parse();
}
ESDS::~ESDS() {
delete[] mData;
mData = NULL;
}
status_t ESDS::InitCheck() const {
return mInitCheck;
}
status_t ESDS::getObjectTypeIndication(uint8_t *objectTypeIndication) const {
if (mInitCheck != OK) {
return mInitCheck;
}
*objectTypeIndication = mObjectTypeIndication;
return OK;
}
status_t ESDS::getCodecSpecificInfo(const void **data, size_t *size) const {
if (mInitCheck != OK) {
return mInitCheck;
}
*data = &mData[mDecoderSpecificOffset];
*size = mDecoderSpecificLength;
return OK;
}
status_t ESDS::skipDescriptorHeader(
size_t offset, size_t size,
uint8_t *tag, size_t *data_offset, size_t *data_size) const {
if (size == 0) {
return ERROR_MALFORMED;
}
*tag = mData[offset++];
--size;
*data_size = 0;
bool more;
do {
if (size == 0) {
return ERROR_MALFORMED;
}
uint8_t x = mData[offset++];
--size;
*data_size = (*data_size << 7) | (x & 0x7f);
more = (x & 0x80) != 0;
}
while (more);
ALOGV("tag=0x%02x data_size=%d", *tag, *data_size);
if (*data_size > size) {
return ERROR_MALFORMED;
}
*data_offset = offset;
return OK;
}
status_t ESDS::parse() {
uint8_t tag;
size_t data_offset;
size_t data_size;
status_t err =
skipDescriptorHeader(0, mSize, &tag, &data_offset, &data_size);
if (err != OK) {
return err;
}
if (tag != kTag_ESDescriptor) {
return ERROR_MALFORMED;
}
return parseESDescriptor(data_offset, data_size);
}
status_t ESDS::parseESDescriptor(size_t offset, size_t size) {
if (size < 3) {
return ERROR_MALFORMED;
}
offset += 2; // skip ES_ID
size -= 2;
unsigned streamDependenceFlag = mData[offset] & 0x80;
unsigned URL_Flag = mData[offset] & 0x40;
unsigned OCRstreamFlag = mData[offset] & 0x20;
++offset;
--size;
if (streamDependenceFlag) {
offset += 2;
size -= 2;
}
if (URL_Flag) {
if (offset >= size) {
return ERROR_MALFORMED;
}
unsigned URLlength = mData[offset];
offset += URLlength + 1;
size -= URLlength + 1;
}
if (OCRstreamFlag) {
offset += 2;
size -= 2;
if ((offset >= size || mData[offset] != kTag_DecoderConfigDescriptor)
&& offset - 2 < size
&& mData[offset - 2] == kTag_DecoderConfigDescriptor) {
// Content found "in the wild" had OCRstreamFlag set but was
// missing OCR_ES_Id, the decoder config descriptor immediately
// followed instead.
offset -= 2;
size += 2;
ALOGW("Found malformed 'esds' atom, ignoring missing OCR_ES_Id.");
}
}
if (offset >= size) {
return ERROR_MALFORMED;
}
uint8_t tag;
size_t sub_offset, sub_size;
status_t err = skipDescriptorHeader(
offset, size, &tag, &sub_offset, &sub_size);
if (err != OK) {
return err;
}
if (tag != kTag_DecoderConfigDescriptor) {
return ERROR_MALFORMED;
}
err = parseDecoderConfigDescriptor(sub_offset, sub_size);
return err;
}
status_t ESDS::parseDecoderConfigDescriptor(size_t offset, size_t size) {
if (size < 13) {
return ERROR_MALFORMED;
}
mObjectTypeIndication = mData[offset];
offset += 13;
size -= 13;
if (size == 0) {
mDecoderSpecificOffset = 0;
mDecoderSpecificLength = 0;
return OK;
}
uint8_t tag;
size_t sub_offset, sub_size;
status_t err = skipDescriptorHeader(
offset, size, &tag, &sub_offset, &sub_size);
if (err != OK) {
return err;
}
if (tag != kTag_DecoderSpecificInfo) {
return ERROR_MALFORMED;
}
mDecoderSpecificOffset = sub_offset;
mDecoderSpecificLength = sub_size;
return OK;
}
} // namespace android