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// Copyright 2019 The libgav1 Authors
//
// 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.
#include "examples/ivf_parser.h"
#include <cstdio>
#include <cstring>
#include "examples/file_reader_constants.h"
#include "examples/logging.h"
namespace libgav1 {
namespace {
size_t ReadLittleEndian16(const uint8_t* const buffer) {
size_t value = buffer[1] << 8;
value |= buffer[0];
return value;
}
size_t ReadLittleEndian32(const uint8_t* const buffer) {
size_t value = buffer[3] << 24;
value |= buffer[2] << 16;
value |= buffer[1] << 8;
value |= buffer[0];
return value;
}
} // namespace
bool ParseIvfFileHeader(const uint8_t* const header_buffer,
IvfFileHeader* const ivf_file_header) {
if (header_buffer == nullptr || ivf_file_header == nullptr) return false;
if (memcmp(kIvfSignature, header_buffer, 4) != 0) {
return false;
}
// Verify header version and length.
const size_t ivf_header_version = ReadLittleEndian16(&header_buffer[4]);
if (ivf_header_version != kIvfHeaderVersion) {
LIBGAV1_EXAMPLES_LOG_ERROR("Unexpected IVF version");
}
const size_t ivf_header_size = ReadLittleEndian16(&header_buffer[6]);
if (ivf_header_size != kIvfFileHeaderSize) {
LIBGAV1_EXAMPLES_LOG_ERROR("Invalid IVF file header size");
return false;
}
if (memcmp(kAv1FourCcLower, &header_buffer[8], 4) != 0 &&
memcmp(kAv1FourCcUpper, &header_buffer[8], 4) != 0) {
LIBGAV1_EXAMPLES_LOG_ERROR("Unsupported codec 4CC");
return false;
}
ivf_file_header->width = ReadLittleEndian16(&header_buffer[12]);
ivf_file_header->height = ReadLittleEndian16(&header_buffer[14]);
ivf_file_header->frame_rate_numerator =
ReadLittleEndian32(&header_buffer[16]);
ivf_file_header->frame_rate_denominator =
ReadLittleEndian32(&header_buffer[20]);
return true;
}
bool ParseIvfFrameHeader(const uint8_t* const header_buffer,
IvfFrameHeader* const ivf_frame_header) {
if (header_buffer == nullptr || ivf_frame_header == nullptr) return false;
ivf_frame_header->frame_size = ReadLittleEndian32(header_buffer);
if (ivf_frame_header->frame_size > kMaxTemporalUnitSize) {
LIBGAV1_EXAMPLES_LOG_ERROR("Temporal Unit size exceeds maximum");
return false;
}
ivf_frame_header->timestamp = ReadLittleEndian32(&header_buffer[4]);
const uint64_t timestamp_hi =
static_cast<uint64_t>(ReadLittleEndian32(&header_buffer[8])) << 32;
ivf_frame_header->timestamp |= timestamp_hi;
return true;
}
} // namespace libgav1
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