blob: 1ce7d24a8e07f29947dea6f3c52cf364e987ae44 [file] [log] [blame]
/*
* Copyright (c) 2017, Alliance for Open Media. All rights reserved
*
* This source code is subject to the terms of the BSD 2 Clause License and
* the Alliance for Open Media Patent License 1.0. If the BSD 2 Clause License
* was not distributed with this source code in the LICENSE file, you can
* obtain it at www.aomedia.org/license/software. If the Alliance for Open
* Media Patent License 1.0 was not distributed with this source code in the
* PATENTS file, you can obtain it at www.aomedia.org/license/patent.
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "./obudec.h"
#include "aom_ports/mem_ops.h"
#include "av1/common/common.h"
#include "av1/decoder/obu.h"
#define OBU_BUFFER_SIZE (500 * 1024)
#define OBU_HEADER_SIZE 1
#define OBU_EXTENSION_SIZE 1
#define OBU_MAX_LENGTH_FIELD_SIZE 8
#define OBU_DETECTION_SIZE \
(OBU_HEADER_SIZE + OBU_EXTENSION_SIZE + OBU_MAX_LENGTH_FIELD_SIZE)
// Reads unsigned LEB128 integer and returns 0 upon successful read and decode.
// Stores raw bytes in 'value_buffer', length of the number in 'value_length',
// and decoded value in 'value'.
static int obudec_read_leb128(FILE *f, uint8_t *value_buffer,
size_t *value_length, uint64_t *value) {
if (!f || !value_buffer || !value_length || !value) return -1;
for (int len = 0; len < OBU_MAX_LENGTH_FIELD_SIZE; ++len) {
const size_t num_read = fread(&value_buffer[len], 1, 1, f);
if (num_read == 0 && feof(f)) {
*value_length = 0;
return 0;
}
if (num_read != 1) {
// Ran out of data before completing read of value.
return -1;
}
if ((value_buffer[len] >> 7) == 0) {
*value_length = (size_t)(len + 1);
break;
}
}
return aom_uleb_decode(value_buffer, OBU_MAX_LENGTH_FIELD_SIZE, value, NULL);
}
// Reads OBU size from infile and returns 0 upon success. Returns obu_size via
// output pointer obu_size. Returns -1 when reading or parsing fails. Always
// returns FILE pointer to position at time of call. Returns 0 and sets obu_size
// to 0 when end of file is reached.
static int obudec_read_obu_size(FILE *infile, uint64_t *obu_size,
size_t *length_field_size) {
if (!infile || !obu_size) return 1;
uint8_t read_buffer[OBU_MAX_LENGTH_FIELD_SIZE] = { 0 };
size_t bytes_read = fread(read_buffer, 1, OBU_MAX_LENGTH_FIELD_SIZE, infile);
*obu_size = 0;
if (bytes_read == 0) {
return 0;
}
const int seek_pos = (int)bytes_read;
if (seek_pos != 0 && fseek(infile, -seek_pos, SEEK_CUR) != 0) return 1;
if (aom_uleb_decode(read_buffer, bytes_read, obu_size, length_field_size) !=
0) {
return 1;
}
return 0;
}
// Reads OBU header from 'f'. The 'buffer_capacity' passed in must be large
// enough to store an OBU header with extension (2 bytes). Raw OBU data is
// written to 'obu_data', parsed OBU header values are written to 'obu_header',
// and total bytes read from file are written to 'bytes_read'. Returns 0 for
// success, and non-zero on failure. When end of file is reached, the return
// value is 0 and the 'bytes_read' value is set to 0.
static int obudec_read_obu_header(FILE *f, size_t buffer_capacity,
int is_annexb, uint8_t *obu_data,
ObuHeader *obu_header, size_t *bytes_read) {
if (!f || buffer_capacity < (OBU_HEADER_SIZE + OBU_EXTENSION_SIZE) ||
!obu_data || !obu_header || !bytes_read) {
return -1;
}
*bytes_read = fread(obu_data, 1, 1, f);
if (feof(f) && *bytes_read == 0) {
return 0;
} else if (*bytes_read != 1) {
fprintf(stderr, "obudec: Failure reading OBU header.\n");
return -1;
}
const int has_extension = (obu_data[0] >> 2) & 0x1;
if (has_extension) {
if (fread(&obu_data[1], 1, 1, f) != 1) {
fprintf(stderr, "obudec: Failure reading OBU extension.");
return -1;
}
++*bytes_read;
}
size_t obu_bytes_parsed = 0;
const aom_codec_err_t parse_result = aom_read_obu_header(
obu_data, *bytes_read, &obu_bytes_parsed, obu_header, is_annexb);
if (parse_result != AOM_CODEC_OK || *bytes_read != obu_bytes_parsed) {
fprintf(stderr, "obudec: Error parsing OBU header.\n");
return -1;
}
return 0;
}
// Reads OBU payload from 'f' and returns 0 for success when all payload bytes
// are read from the file. Payload data is written to 'obu_data', and actual
// bytes read written to 'bytes_read'.
static int obudec_read_obu_payload(FILE *f, uint64_t payload_length,
uint8_t *obu_data, size_t *bytes_read) {
if (!f || payload_length == 0 || !obu_data || !bytes_read) return -1;
if (fread(obu_data, 1, (size_t)payload_length, f) != payload_length) {
fprintf(stderr, "obudec: Failure reading OBU payload.\n");
return -1;
}
*bytes_read += payload_length;
return 0;
}
static int obudec_read_one_obu(FILE *f, size_t buffer_capacity, int is_annexb,
uint8_t *obu_data, uint64_t *obu_length,
ObuHeader *obu_header) {
const size_t kMinimumBufferSize = OBU_DETECTION_SIZE;
if (!f || !obu_data || !obu_length || !obu_header ||
buffer_capacity < kMinimumBufferSize) {
return -1;
}
uint64_t obu_payload_length = 0;
size_t leb128_length = 0;
uint64_t obu_size = 0;
if (is_annexb) {
if (obudec_read_leb128(f, &obu_data[0], &leb128_length, &obu_size) != 0) {
fprintf(stderr, "obudec: Failure reading OBU size length.\n");
return -1;
} else if (leb128_length == 0) {
*obu_length = 0;
return 0;
}
}
size_t bytes_read = 0;
if (obudec_read_obu_header(f, buffer_capacity, is_annexb,
obu_data + leb128_length, obu_header,
&bytes_read) != 0) {
return -1;
} else if (bytes_read == 0) {
*obu_length = 0;
return 0;
}
if (!is_annexb) {
if (obudec_read_leb128(f, &obu_data[bytes_read], &leb128_length,
&obu_payload_length) != 0) {
fprintf(stderr, "obudec: Failure reading OBU payload length.\n");
return -1;
}
}
if (is_annexb) {
obu_payload_length = obu_size - bytes_read;
}
bytes_read += leb128_length;
if (UINT64_MAX - bytes_read < obu_payload_length) return -1;
if (bytes_read + obu_payload_length > buffer_capacity) {
*obu_length = bytes_read + obu_payload_length;
return -1;
}
if (obu_payload_length > 0 &&
obudec_read_obu_payload(f, obu_payload_length, &obu_data[bytes_read],
&bytes_read) != 0) {
return -1;
}
*obu_length = bytes_read;
return 0;
}
int file_is_obu(struct ObuDecInputContext *obu_ctx) {
if (!obu_ctx || !obu_ctx->avx_ctx) return 0;
struct AvxInputContext *avx_ctx = obu_ctx->avx_ctx;
uint8_t detect_buf[OBU_DETECTION_SIZE] = { 0 };
const int is_annexb = obu_ctx->is_annexb;
FILE *f = avx_ctx->file;
uint64_t obu_length = 0;
ObuHeader obu_header;
memset(&obu_header, 0, sizeof(obu_header));
if (obudec_read_one_obu(f, OBU_DETECTION_SIZE, is_annexb, &detect_buf[0],
&obu_length, &obu_header) != 0) {
fprintf(stderr, "obudec: Failure reading first OBU.\n");
rewind(f);
return 0;
}
if (obu_header.type != OBU_TEMPORAL_DELIMITER) return 0;
if (obu_header.has_length_field) {
uint64_t obu_payload_length = 0;
size_t leb128_length = 0;
const size_t obu_length_offset = obu_header.has_length_field ? 1 : 2;
if (aom_uleb_decode(&detect_buf[obu_length_offset], sizeof(leb128_length),
&obu_payload_length, &leb128_length) != 0) {
fprintf(stderr, "obudec: Failure decoding OBU payload length.\n");
rewind(f);
return 0;
}
if (obu_payload_length != 0) {
fprintf(
stderr,
"obudec: Invalid OBU_TEMPORAL_DELIMITER payload length (non-zero).");
rewind(f);
return 0;
}
} else if (!is_annexb) {
fprintf(stderr, "obudec: OBU size fields required, cannot decode input.\n");
rewind(f);
return (0);
}
// Appears that input is valid Section 5 AV1 stream.
obu_ctx->buffer = (uint8_t *)calloc(OBU_BUFFER_SIZE, 1);
if (!obu_ctx->buffer) {
fprintf(stderr, "Out of memory.\n");
rewind(f);
return 0;
}
obu_ctx->buffer_capacity = OBU_BUFFER_SIZE;
memcpy(obu_ctx->buffer, &detect_buf[0], (size_t)obu_length);
obu_ctx->bytes_buffered = (size_t)obu_length;
return 1;
}
int obudec_read_temporal_unit(struct ObuDecInputContext *obu_ctx,
uint8_t **buffer, size_t *bytes_read,
size_t *buffer_size, int last_layer_id) {
FILE *f = obu_ctx->avx_ctx->file;
if (!f) return -1;
*buffer_size = 0;
*bytes_read = 0;
if (feof(f)) {
return 1;
}
const int is_annexb = obu_ctx->is_annexb;
while (1) {
ObuHeader obu_header;
memset(&obu_header, 0, sizeof(obu_header));
uint64_t obu_size = 0;
uint8_t *data = obu_ctx->buffer + obu_ctx->bytes_buffered;
const size_t capacity = obu_ctx->buffer_capacity - obu_ctx->bytes_buffered;
if (obudec_read_one_obu(f, capacity, is_annexb, data, &obu_size,
&obu_header) != 0) {
fprintf(stderr, "obudec: read_one_obu failed in TU loop\n");
return -1;
}
if (obu_header.type == OBU_TEMPORAL_DELIMITER || obu_size == 0 ||
(obu_header.has_extension &&
obu_header.enhancement_layer_id > last_layer_id)) {
const size_t tu_size = obu_ctx->bytes_buffered;
#if defined AOM_MAX_ALLOCABLE_MEMORY
if (tu_size > AOM_MAX_ALLOCABLE_MEMORY) {
fprintf(stderr, "obudec: Temporal Unit size exceeds max alloc size.\n");
return -1;
}
#endif
uint8_t *new_buffer = (uint8_t *)realloc(*buffer, tu_size);
if (!new_buffer) {
free(*buffer);
fprintf(stderr, "obudec: Out of memory.\n");
return -1;
}
*buffer = new_buffer;
*bytes_read = tu_size;
*buffer_size = tu_size;
memcpy(*buffer, obu_ctx->buffer, tu_size);
memmove(obu_ctx->buffer, data, (size_t)obu_size);
obu_ctx->bytes_buffered = (size_t)obu_size;
break;
} else {
obu_ctx->bytes_buffered += (size_t)obu_size;
}
}
return 0;
}
void obudec_free(struct ObuDecInputContext *obu_ctx) { free(obu_ctx->buffer); }