ref: 2bc9ba828f5c2d4663478bd94e125101851d1e9c
dir: /tools/input/annexb.c/
/* * Copyright © 2018, VideoLAN and dav1d authors * Copyright © 2018, Two Orioles, LLC * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions are met: * * 1. Redistributions of source code must retain the above copyright notice, this * list of conditions and the following disclaimer. * * 2. Redistributions in binary form must reproduce the above copyright notice, * this list of conditions and the following disclaimer in the documentation * and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ #include "config.h" #include <assert.h> #include <errno.h> #include <stdio.h> #include <stdint.h> #include <stdlib.h> #include <string.h> #include "input/demuxer.h" typedef struct DemuxerPriv { FILE *f; size_t temporal_unit_size; size_t frame_unit_size; } AnnexbInputContext; static int leb128(AnnexbInputContext *const c, size_t *const len) { unsigned more, i = 0; uint8_t byte; *len = 0; do { if (fread(&byte, 1, 1, c->f) < 1) return -1; more = byte & 0x80; unsigned bits = byte & 0x7f; if (i <= 3 || (i == 4 && bits < (1 << 4))) *len |= bits << (i * 7); else if (bits) return -1; if (++i == 8 && more) return -1; } while (more); return i; } static int annexb_open(AnnexbInputContext *const c, const char *const file, unsigned fps[2], unsigned *const num_frames) { int res; size_t len; if (!(c->f = fopen(file, "rb"))) { fprintf(stderr, "Failed to open %s: %s\n", file, strerror(errno)); return -1; } // TODO: Parse sequence header and read timing info if any. fps[0] = 25; fps[1] = 1; for (*num_frames = 0;; (*num_frames)++) { res = leb128(c, &len); if (res < 0) break; fseek(c->f, len, SEEK_CUR); } fseek(c->f, 0, SEEK_SET); return 0; } static int annexb_read(AnnexbInputContext *const c, Dav1dData *const data) { size_t len; int res; if (!c->temporal_unit_size) { res = leb128(c, &c->temporal_unit_size); if (res < 0) return -1; } if (!c->frame_unit_size) { res = leb128(c, &c->frame_unit_size); if (res < 0 || (c->frame_unit_size + res) > c->temporal_unit_size) return -1; c->temporal_unit_size -= res; } res = leb128(c, &len); if (res < 0 || (len + res) > c->frame_unit_size) return -1; uint8_t *ptr = dav1d_data_create(data, len); if (!ptr) return -1; c->temporal_unit_size -= len + res; c->frame_unit_size -= len + res; if (fread(ptr, len, 1, c->f) != 1) { fprintf(stderr, "Failed to read frame data: %s\n", strerror(errno)); dav1d_data_unref(data); return -1; } return 0; } static void annexb_close(AnnexbInputContext *const c) { fclose(c->f); } const Demuxer annexb_demuxer = { .priv_data_size = sizeof(AnnexbInputContext), .name = "annexb", .extension = "obu", .open = annexb_open, .read = annexb_read, .close = annexb_close, };