diff options
Diffstat (limited to 'media/libaom/src/common/obudec.c')
| -rw-r--r-- | media/libaom/src/common/obudec.c | 448 |
1 files changed, 448 insertions, 0 deletions
diff --git a/media/libaom/src/common/obudec.c b/media/libaom/src/common/obudec.c new file mode 100644 index 000000000..acbd12e0c --- /dev/null +++ b/media/libaom/src/common/obudec.c @@ -0,0 +1,448 @@ +/* + * 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 "common/obudec.h" + +#include "aom_ports/mem_ops.h" +#include "av1/common/common.h" +#include "av1/common/obu_util.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 + 3 * 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; + size_t len; + for (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) { + if (len == 0 && feof(f)) { + *value_length = 0; + return 0; + } + // Ran out of data before completing read of value. + return -1; + } + if ((value_buffer[len] >> 7) == 0) { + ++len; + *value_length = len; + break; + } + } + + return aom_uleb_decode(value_buffer, len, value, NULL); +} + +// 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 added to 'bytes_read'. +static int obudec_read_obu_payload(FILE *f, size_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, 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_obu_header_and_size(FILE *f, size_t buffer_capacity, + int is_annexb, uint8_t *buffer, + size_t *bytes_read, + size_t *payload_length, + ObuHeader *obu_header) { + const size_t kMinimumBufferSize = + (OBU_HEADER_SIZE + OBU_EXTENSION_SIZE + OBU_MAX_LENGTH_FIELD_SIZE); + if (!f || !buffer || !bytes_read || !payload_length || !obu_header || + buffer_capacity < kMinimumBufferSize) { + return -1; + } + + size_t leb128_length = 0; + uint64_t obu_size = 0; + if (is_annexb) { + if (obudec_read_leb128(f, &buffer[0], &leb128_length, &obu_size) != 0) { + fprintf(stderr, "obudec: Failure reading OBU size length.\n"); + return -1; + } else if (leb128_length == 0) { + *payload_length = 0; + return 0; + } + if (obu_size > UINT32_MAX) { + fprintf(stderr, "obudec: OBU payload length too large.\n"); + return -1; + } + } + + size_t header_size = 0; + if (obudec_read_obu_header(f, buffer_capacity - leb128_length, is_annexb, + buffer + leb128_length, obu_header, + &header_size) != 0) { + return -1; + } else if (header_size == 0) { + *payload_length = 0; + return 0; + } + + if (is_annexb) { + if (obu_size < header_size) { + fprintf(stderr, "obudec: OBU size is too small.\n"); + return -1; + } + *payload_length = (size_t)obu_size - header_size; + } else { + uint64_t u64_payload_length = 0; + if (obudec_read_leb128(f, &buffer[header_size], &leb128_length, + &u64_payload_length) != 0) { + fprintf(stderr, "obudec: Failure reading OBU payload length.\n"); + return -1; + } + if (u64_payload_length > UINT32_MAX) { + fprintf(stderr, "obudec: OBU payload length too large.\n"); + return -1; + } + + *payload_length = (size_t)u64_payload_length; + } + + *bytes_read = leb128_length + header_size; + return 0; +} + +static int obudec_read_one_obu(FILE *f, uint8_t **obu_buffer, + size_t obu_bytes_buffered, + size_t *obu_buffer_capacity, size_t *obu_length, + ObuHeader *obu_header, int is_annexb) { + size_t available_buffer_capacity = *obu_buffer_capacity - obu_bytes_buffered; + + if (!(*obu_buffer)) return -1; + + size_t bytes_read = 0; + size_t obu_payload_length = 0; + const int status = obudec_read_obu_header_and_size( + f, available_buffer_capacity, is_annexb, *obu_buffer + obu_bytes_buffered, + &bytes_read, &obu_payload_length, obu_header); + if (status < 0) return status; + + if (obu_payload_length > SIZE_MAX - bytes_read) return -1; + + if (obu_payload_length > 256 * 1024 * 1024) { + fprintf(stderr, "obudec: Read invalid OBU size (%u)\n", + (unsigned int)obu_payload_length); + *obu_length = bytes_read + obu_payload_length; + return -1; + } + + if (bytes_read + obu_payload_length > available_buffer_capacity) { + // TODO(tomfinegan): Add overflow check. + const size_t new_capacity = + obu_bytes_buffered + bytes_read + 2 * obu_payload_length; + +#if defined AOM_MAX_ALLOCABLE_MEMORY + if (new_capacity > AOM_MAX_ALLOCABLE_MEMORY) { + fprintf(stderr, "obudec: OBU size exceeds max alloc size.\n"); + return -1; + } +#endif + + uint8_t *new_buffer = (uint8_t *)realloc(*obu_buffer, new_capacity); + + if (new_buffer) { + *obu_buffer = new_buffer; + *obu_buffer_capacity = new_capacity; + } else { + fprintf(stderr, "obudec: Failed to allocate compressed data buffer\n"); + *obu_length = bytes_read + obu_payload_length; + return -1; + } + } + + if (obu_payload_length > 0 && + obudec_read_obu_payload(f, obu_payload_length, + *obu_buffer + obu_bytes_buffered + 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; + size_t payload_length = 0; + ObuHeader obu_header; + memset(&obu_header, 0, sizeof(obu_header)); + size_t length_of_unit_size = 0; + size_t annexb_header_length = 0; + uint64_t unit_size = 0; + + if (is_annexb) { + // read the size of first temporal unit + if (obudec_read_leb128(f, &detect_buf[0], &length_of_unit_size, + &unit_size) != 0) { + fprintf(stderr, "obudec: Failure reading temporal unit header\n"); + return 0; + } + + // read the size of first frame unit + if (obudec_read_leb128(f, &detect_buf[length_of_unit_size], + &annexb_header_length, &unit_size) != 0) { + fprintf(stderr, "obudec: Failure reading frame unit header\n"); + return 0; + } + annexb_header_length += length_of_unit_size; + } + + size_t bytes_read = 0; + if (obudec_read_obu_header_and_size( + f, OBU_DETECTION_SIZE - annexb_header_length, is_annexb, + &detect_buf[annexb_header_length], &bytes_read, &payload_length, + &obu_header) != 0) { + fprintf(stderr, "obudec: Failure reading first OBU.\n"); + rewind(f); + return 0; + } + + if (is_annexb) { + bytes_read += annexb_header_length; + } + + if (obu_header.type != OBU_TEMPORAL_DELIMITER && + obu_header.type != OBU_SEQUENCE_HEADER) { + return 0; + } + + if (obu_header.has_size_field) { + if (obu_header.type == OBU_TEMPORAL_DELIMITER && 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 *)malloc(OBU_BUFFER_SIZE); + 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], bytes_read); + obu_ctx->bytes_buffered = bytes_read; + // If the first OBU is a SEQUENCE_HEADER, then it will have a payload. + // We need to read this in so that our buffer only contains complete OBUs. + if (payload_length > 0) { + if (payload_length > (obu_ctx->buffer_capacity - bytes_read)) { + fprintf(stderr, "obudec: First OBU's payload is too large\n"); + rewind(f); + return 0; + } + + size_t payload_bytes = 0; + const int status = obudec_read_obu_payload( + f, payload_length, &obu_ctx->buffer[bytes_read], &payload_bytes); + if (status < 0) { + rewind(f); + return 0; + } + obu_ctx->bytes_buffered += payload_bytes; + } + return 1; +} + +int obudec_read_temporal_unit(struct ObuDecInputContext *obu_ctx, + uint8_t **buffer, size_t *bytes_read, + size_t *buffer_size) { + FILE *f = obu_ctx->avx_ctx->file; + if (!f) return -1; + + *buffer_size = 0; + *bytes_read = 0; + + if (feof(f)) { + return 1; + } + + size_t tu_size; + size_t obu_size = 0; + size_t length_of_temporal_unit_size = 0; + uint8_t tuheader[OBU_MAX_LENGTH_FIELD_SIZE] = { 0 }; + + if (obu_ctx->is_annexb) { + uint64_t size = 0; + + if (obu_ctx->bytes_buffered == 0) { + if (obudec_read_leb128(f, &tuheader[0], &length_of_temporal_unit_size, + &size) != 0) { + fprintf(stderr, "obudec: Failure reading temporal unit header\n"); + return -1; + } + if (size == 0 && feof(f)) { + return 1; + } + } else { + // temporal unit size was already stored in buffer + if (aom_uleb_decode(obu_ctx->buffer, obu_ctx->bytes_buffered, &size, + &length_of_temporal_unit_size) != 0) { + fprintf(stderr, "obudec: Failure reading temporal unit header\n"); + return -1; + } + } + + if (size > UINT32_MAX || size + length_of_temporal_unit_size > UINT32_MAX) { + fprintf(stderr, "obudec: TU too large.\n"); + return -1; + } + + size += length_of_temporal_unit_size; + tu_size = (size_t)size; + } else { + while (1) { + ObuHeader obu_header; + memset(&obu_header, 0, sizeof(obu_header)); + + if (obudec_read_one_obu(f, &obu_ctx->buffer, obu_ctx->bytes_buffered, + &obu_ctx->buffer_capacity, &obu_size, &obu_header, + 0) != 0) { + fprintf(stderr, "obudec: read_one_obu failed in TU loop\n"); + return -1; + } + + if (obu_header.type == OBU_TEMPORAL_DELIMITER || obu_size == 0) { + tu_size = obu_ctx->bytes_buffered; + break; + } else { + obu_ctx->bytes_buffered += obu_size; + } + } + } + +#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; + + if (!obu_ctx->is_annexb) { + memcpy(*buffer, obu_ctx->buffer, tu_size); + + // At this point, (obu_ctx->buffer + obu_ctx->bytes_buffered + obu_size) + // points to the end of the buffer. + memmove(obu_ctx->buffer, obu_ctx->buffer + obu_ctx->bytes_buffered, + obu_size); + obu_ctx->bytes_buffered = obu_size; + } else { + if (!feof(f)) { + size_t data_size; + size_t offset; + if (!obu_ctx->bytes_buffered) { + data_size = tu_size - length_of_temporal_unit_size; + memcpy(*buffer, &tuheader[0], length_of_temporal_unit_size); + offset = length_of_temporal_unit_size; + } else { + memcpy(*buffer, obu_ctx->buffer, obu_ctx->bytes_buffered); + offset = obu_ctx->bytes_buffered; + data_size = tu_size - obu_ctx->bytes_buffered; + obu_ctx->bytes_buffered = 0; + } + + if (fread(*buffer + offset, 1, data_size, f) != data_size) { + fprintf(stderr, "obudec: Failed to read full temporal unit\n"); + return -1; + } + } + } + return 0; +} + +void obudec_free(struct ObuDecInputContext *obu_ctx) { free(obu_ctx->buffer); } |