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Diffstat (limited to 'ffmpeg1/libavformat/mxg.c')
-rw-r--r--ffmpeg1/libavformat/mxg.c260
1 files changed, 0 insertions, 260 deletions
diff --git a/ffmpeg1/libavformat/mxg.c b/ffmpeg1/libavformat/mxg.c
deleted file mode 100644
index 604be78..0000000
--- a/ffmpeg1/libavformat/mxg.c
+++ /dev/null
@@ -1,260 +0,0 @@
-/*
- * MxPEG clip file demuxer
- * Copyright (c) 2010 Anatoly Nenashev
- *
- * 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
- */
-
-#include "libavutil/channel_layout.h"
-#include "libavutil/intreadwrite.h"
-#include "libavcodec/mjpeg.h"
-#include "avformat.h"
-#include "internal.h"
-#include "avio.h"
-
-#define DEFAULT_PACKET_SIZE 1024
-#define OVERREAD_SIZE 3
-
-typedef struct MXGContext {
- uint8_t *buffer;
- uint8_t *buffer_ptr;
- uint8_t *soi_ptr;
- unsigned int buffer_size;
- int64_t dts;
- unsigned int cache_size;
-} MXGContext;
-
-static int mxg_read_header(AVFormatContext *s)
-{
- AVStream *video_st, *audio_st;
- MXGContext *mxg = s->priv_data;
-
- /* video parameters will be extracted from the compressed bitstream */
- video_st = avformat_new_stream(s, NULL);
- if (!video_st)
- return AVERROR(ENOMEM);
- video_st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
- video_st->codec->codec_id = AV_CODEC_ID_MXPEG;
- avpriv_set_pts_info(video_st, 64, 1, 1000000);
-
- audio_st = avformat_new_stream(s, NULL);
- if (!audio_st)
- return AVERROR(ENOMEM);
- audio_st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
- audio_st->codec->codec_id = AV_CODEC_ID_PCM_ALAW;
- audio_st->codec->channels = 1;
- audio_st->codec->channel_layout = AV_CH_LAYOUT_MONO;
- audio_st->codec->sample_rate = 8000;
- audio_st->codec->bits_per_coded_sample = 8;
- audio_st->codec->block_align = 1;
- avpriv_set_pts_info(audio_st, 64, 1, 1000000);
-
- mxg->soi_ptr = mxg->buffer_ptr = mxg->buffer = 0;
- mxg->buffer_size = 0;
- mxg->dts = AV_NOPTS_VALUE;
- mxg->cache_size = 0;
-
- return 0;
-}
-
-static uint8_t* mxg_find_startmarker(uint8_t *p, uint8_t *end)
-{
- for (; p < end - 3; p += 4) {
- uint32_t x = *(uint32_t*)p;
-
- if (x & (~(x+0x01010101)) & 0x80808080) {
- if (p[0] == 0xff) {
- return p;
- } else if (p[1] == 0xff) {
- return p+1;
- } else if (p[2] == 0xff) {
- return p+2;
- } else if (p[3] == 0xff) {
- return p+3;
- }
- }
- }
-
- for (; p < end; ++p) {
- if (*p == 0xff) return p;
- }
-
- return end;
-}
-
-static int mxg_update_cache(AVFormatContext *s, unsigned int cache_size)
-{
- MXGContext *mxg = s->priv_data;
- unsigned int current_pos = mxg->buffer_ptr - mxg->buffer;
- unsigned int soi_pos;
- uint8_t *buffer;
- int ret;
-
- /* reallocate internal buffer */
- if (current_pos > current_pos + cache_size)
- return AVERROR(ENOMEM);
- soi_pos = mxg->soi_ptr - mxg->buffer;
- buffer = av_fast_realloc(mxg->buffer, &mxg->buffer_size,
- current_pos + cache_size +
- FF_INPUT_BUFFER_PADDING_SIZE);
- if (!buffer)
- return AVERROR(ENOMEM);
- mxg->buffer = buffer;
- mxg->buffer_ptr = mxg->buffer + current_pos;
- if (mxg->soi_ptr) mxg->soi_ptr = mxg->buffer + soi_pos;
-
- /* get data */
- ret = avio_read(s->pb, mxg->buffer_ptr + mxg->cache_size,
- cache_size - mxg->cache_size);
- if (ret < 0)
- return ret;
-
- mxg->cache_size += ret;
-
- return ret;
-}
-
-static int mxg_read_packet(AVFormatContext *s, AVPacket *pkt)
-{
- int ret;
- unsigned int size;
- uint8_t *startmarker_ptr, *end, *search_end, marker;
- MXGContext *mxg = s->priv_data;
-
- while (!url_feof(s->pb) && !s->pb->error){
- if (mxg->cache_size <= OVERREAD_SIZE) {
- /* update internal buffer */
- ret = mxg_update_cache(s, DEFAULT_PACKET_SIZE + OVERREAD_SIZE);
- if (ret < 0)
- return ret;
- }
- end = mxg->buffer_ptr + mxg->cache_size;
-
- /* find start marker - 0xff */
- if (mxg->cache_size > OVERREAD_SIZE) {
- search_end = end - OVERREAD_SIZE;
- startmarker_ptr = mxg_find_startmarker(mxg->buffer_ptr, search_end);
- } else {
- search_end = end;
- startmarker_ptr = mxg_find_startmarker(mxg->buffer_ptr, search_end);
- if (startmarker_ptr >= search_end - 1 ||
- *(startmarker_ptr + 1) != EOI) break;
- }
-
- if (startmarker_ptr != search_end) { /* start marker found */
- marker = *(startmarker_ptr + 1);
- mxg->buffer_ptr = startmarker_ptr + 2;
- mxg->cache_size = end - mxg->buffer_ptr;
-
- if (marker == SOI) {
- mxg->soi_ptr = startmarker_ptr;
- } else if (marker == EOI) {
- if (!mxg->soi_ptr) {
- av_log(s, AV_LOG_WARNING, "Found EOI before SOI, skipping\n");
- continue;
- }
-
- pkt->pts = pkt->dts = mxg->dts;
- pkt->stream_index = 0;
-#if FF_API_DESTRUCT_PACKET
- pkt->destruct = NULL;
-#endif
- pkt->buf = NULL;
- pkt->size = mxg->buffer_ptr - mxg->soi_ptr;
- pkt->data = mxg->soi_ptr;
-
- if (mxg->soi_ptr - mxg->buffer > mxg->cache_size) {
- if (mxg->cache_size > 0) {
- memcpy(mxg->buffer, mxg->buffer_ptr, mxg->cache_size);
- }
-
- mxg->buffer_ptr = mxg->buffer;
- }
- mxg->soi_ptr = 0;
-
- return pkt->size;
- } else if ( (SOF0 <= marker && marker <= SOF15) ||
- (SOS <= marker && marker <= COM) ) {
- /* all other markers that start marker segment also contain
- length value (see specification for JPEG Annex B.1) */
- size = AV_RB16(mxg->buffer_ptr);
- if (size < 2)
- return AVERROR(EINVAL);
-
- if (mxg->cache_size < size) {
- ret = mxg_update_cache(s, size);
- if (ret < 0)
- return ret;
- startmarker_ptr = mxg->buffer_ptr - 2;
- mxg->cache_size = 0;
- } else {
- mxg->cache_size -= size;
- }
-
- mxg->buffer_ptr += size;
-
- if (marker == APP13 && size >= 16) { /* audio data */
- /* time (GMT) of first sample in usec since 1970, little-endian */
- pkt->pts = pkt->dts = AV_RL64(startmarker_ptr + 8);
- pkt->stream_index = 1;
-#if FF_API_DESTRUCT_PACKET
- pkt->destruct = NULL;
-#endif
- pkt->buf = NULL;
- pkt->size = size - 14;
- pkt->data = startmarker_ptr + 16;
-
- if (startmarker_ptr - mxg->buffer > mxg->cache_size) {
- if (mxg->cache_size > 0) {
- memcpy(mxg->buffer, mxg->buffer_ptr, mxg->cache_size);
- }
- mxg->buffer_ptr = mxg->buffer;
- }
-
- return pkt->size;
- } else if (marker == COM && size >= 18 &&
- !strncmp(startmarker_ptr + 4, "MXF", 3)) {
- /* time (GMT) of video frame in usec since 1970, little-endian */
- mxg->dts = AV_RL64(startmarker_ptr + 12);
- }
- }
- } else {
- /* start marker not found */
- mxg->buffer_ptr = search_end;
- mxg->cache_size = OVERREAD_SIZE;
- }
- }
-
- return AVERROR_EOF;
-}
-
-static int mxg_close(struct AVFormatContext *s)
-{
- MXGContext *mxg = s->priv_data;
- av_freep(&mxg->buffer);
- return 0;
-}
-
-AVInputFormat ff_mxg_demuxer = {
- .name = "mxg",
- .long_name = NULL_IF_CONFIG_SMALL("MxPEG clip"),
- .priv_data_size = sizeof(MXGContext),
- .read_header = mxg_read_header,
- .read_packet = mxg_read_packet,
- .read_close = mxg_close,
- .extensions = "mxg",
-};
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