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Diffstat (limited to 'ffmpeg1/libavcodec/dirac_parser.c')
-rw-r--r--ffmpeg1/libavcodec/dirac_parser.c260
1 files changed, 0 insertions, 260 deletions
diff --git a/ffmpeg1/libavcodec/dirac_parser.c b/ffmpeg1/libavcodec/dirac_parser.c
deleted file mode 100644
index a2a22ee..0000000
--- a/ffmpeg1/libavcodec/dirac_parser.c
+++ /dev/null
@@ -1,260 +0,0 @@
-/*
- * Dirac parser
- *
- * Copyright (c) 2007-2008 Marco Gerards <marco@gnu.org>
- * Copyright (c) 2008 BBC, Anuradha Suraparaju <asuraparaju@gmail.com>
- *
- * This file is part of FFmpeg.
- *
- * FFmpeg is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; either
- * version 2.1 of the License, or (at your option) any later version.
- *
- * FFmpeg is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with FFmpeg; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
- */
-
-/**
- * @file
- * Dirac Parser
- * @author Marco Gerards <marco@gnu.org>
- */
-
-#include <string.h>
-
-#include "libavutil/intreadwrite.h"
-#include "libavutil/mem.h"
-#include "parser.h"
-
-#define DIRAC_PARSE_INFO_PREFIX 0x42424344
-
-/**
- * Find the end of the current frame in the bitstream.
- * @return the position of the first byte of the next frame or -1
- */
-typedef struct DiracParseContext {
- int state;
- int is_synced;
- int sync_offset;
- int header_bytes_needed;
- int overread_index;
- int buffer_size;
- int index;
- uint8_t *buffer;
- int dirac_unit_size;
- uint8_t *dirac_unit;
-} DiracParseContext;
-
-static int find_frame_end(DiracParseContext *pc,
- const uint8_t *buf, int buf_size)
-{
- uint32_t state = pc->state;
- int i = 0;
-
- if (!pc->is_synced) {
- for (i = 0; i < buf_size; i++) {
- state = (state << 8) | buf[i];
- if (state == DIRAC_PARSE_INFO_PREFIX) {
- state = -1;
- pc->is_synced = 1;
- pc->header_bytes_needed = 9;
- pc->sync_offset = i;
- break;
- }
- }
- }
-
- if (pc->is_synced) {
- pc->sync_offset = 0;
- for (; i < buf_size; i++) {
- if (state == DIRAC_PARSE_INFO_PREFIX) {
- if ((buf_size-i) >= pc->header_bytes_needed) {
- pc->state = -1;
- return i + pc->header_bytes_needed;
- } else {
- pc->header_bytes_needed = 9-(buf_size-i);
- break;
- }
- } else
- state = (state << 8) | buf[i];
- }
- }
- pc->state = state;
- return -1;
-}
-
-typedef struct DiracParseUnit
-{
- int next_pu_offset;
- int prev_pu_offset;
- uint8_t pu_type;
-} DiracParseUnit;
-
-static int unpack_parse_unit(DiracParseUnit *pu, DiracParseContext *pc,
- int offset)
-{
- uint8_t *start = pc->buffer + offset;
- uint8_t *end = pc->buffer + pc->index;
- if (start < pc->buffer || (start+13 > end))
- return 0;
- pu->pu_type = start[4];
-
- pu->next_pu_offset = AV_RB32(start+5);
- pu->prev_pu_offset = AV_RB32(start+9);
-
- if (pu->pu_type == 0x10 && pu->next_pu_offset == 0)
- pu->next_pu_offset = 13;
-
- return 1;
-}
-
-static int dirac_combine_frame(AVCodecParserContext *s, AVCodecContext *avctx,
- int next, const uint8_t **buf, int *buf_size)
-{
- int parse_timing_info = (s->pts == AV_NOPTS_VALUE &&
- s->dts == AV_NOPTS_VALUE);
- DiracParseContext *pc = s->priv_data;
-
- if (pc->overread_index) {
- memcpy(pc->buffer, pc->buffer + pc->overread_index,
- pc->index - pc->overread_index);
- pc->index -= pc->overread_index;
- pc->overread_index = 0;
- if (*buf_size == 0 && pc->buffer[4] == 0x10) {
- *buf = pc->buffer;
- *buf_size = pc->index;
- return 0;
- }
- }
-
- if ( next == -1) {
- /* Found a possible frame start but not a frame end */
- void *new_buffer = av_fast_realloc(pc->buffer, &pc->buffer_size,
- pc->index + (*buf_size -
- pc->sync_offset));
- pc->buffer = new_buffer;
- memcpy(pc->buffer+pc->index, (*buf + pc->sync_offset),
- *buf_size - pc->sync_offset);
- pc->index += *buf_size - pc->sync_offset;
- return -1;
- } else {
- /* Found a possible frame start and a possible frame end */
- DiracParseUnit pu1, pu;
- void *new_buffer = av_fast_realloc(pc->buffer, &pc->buffer_size,
- pc->index + next);
- pc->buffer = new_buffer;
- memcpy(pc->buffer + pc->index, *buf, next);
- pc->index += next;
-
- /* Need to check if we have a valid Parse Unit. We can't go by the
- * sync pattern 'BBCD' alone because arithmetic coding of the residual
- * and motion data can cause the pattern triggering a false start of
- * frame. So check if the previous parse offset of the next parse unit
- * is equal to the next parse offset of the current parse unit then
- * we can be pretty sure that we have a valid parse unit */
- if (!unpack_parse_unit(&pu1, pc, pc->index - 13) ||
- !unpack_parse_unit(&pu, pc, pc->index - 13 - pu1.prev_pu_offset) ||
- pu.next_pu_offset != pu1.prev_pu_offset ||
- pc->index < pc->dirac_unit_size + 13LL + pu1.prev_pu_offset
- ) {
- pc->index -= 9;
- *buf_size = next-9;
- pc->header_bytes_needed = 9;
- return -1;
- }
-
- /* All non-frame data must be accompanied by frame data. This is to
- * ensure that pts is set correctly. So if the current parse unit is
- * not frame data, wait for frame data to come along */
-
- pc->dirac_unit = pc->buffer + pc->index - 13 -
- pu1.prev_pu_offset - pc->dirac_unit_size;
-
- pc->dirac_unit_size += pu.next_pu_offset;
-
- if ((pu.pu_type&0x08) != 0x08) {
- pc->header_bytes_needed = 9;
- *buf_size = next;
- return -1;
- }
-
- /* Get the picture number to set the pts and dts*/
- if (parse_timing_info) {
- uint8_t *cur_pu = pc->buffer +
- pc->index - 13 - pu1.prev_pu_offset;
- int pts = AV_RB32(cur_pu + 13);
- if (s->last_pts == 0 && s->last_dts == 0)
- s->dts = pts - 1;
- else
- s->dts = s->last_dts+1;
- s->pts = pts;
- if (!avctx->has_b_frames && (cur_pu[4] & 0x03))
- avctx->has_b_frames = 1;
- }
- if (avctx->has_b_frames && s->pts == s->dts)
- s->pict_type = AV_PICTURE_TYPE_B;
-
- /* Finally have a complete Dirac data unit */
- *buf = pc->dirac_unit;
- *buf_size = pc->dirac_unit_size;
-
- pc->dirac_unit_size = 0;
- pc->overread_index = pc->index-13;
- pc->header_bytes_needed = 9;
- }
- return next;
-}
-
-static int dirac_parse(AVCodecParserContext *s, AVCodecContext *avctx,
- const uint8_t **poutbuf, int *poutbuf_size,
- const uint8_t *buf, int buf_size)
-{
- DiracParseContext *pc = s->priv_data;
- int next;
-
- *poutbuf = NULL;
- *poutbuf_size = 0;
-
- if (s->flags & PARSER_FLAG_COMPLETE_FRAMES) {
- next = buf_size;
- *poutbuf = buf;
- *poutbuf_size = buf_size;
- /* Assume that data has been packetized into an encapsulation unit. */
- } else {
- next = find_frame_end(pc, buf, buf_size);
- if (!pc->is_synced && next == -1) {
- /* No frame start found yet. So throw away the entire buffer. */
- return buf_size;
- }
-
- if (dirac_combine_frame(s, avctx, next, &buf, &buf_size) < 0) {
- return buf_size;
- }
- }
-
- *poutbuf = buf;
- *poutbuf_size = buf_size;
- return next;
-}
-
-static void dirac_parse_close(AVCodecParserContext *s)
-{
- DiracParseContext *pc = s->priv_data;
-
- if (pc->buffer_size > 0)
- av_free(pc->buffer);
-}
-
-AVCodecParser ff_dirac_parser = {
- .codec_ids = { AV_CODEC_ID_DIRAC },
- .priv_data_size = sizeof(DiracParseContext),
- .parser_parse = dirac_parse,
- .parser_close = dirac_parse_close,
-};
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