[SCM] libav/experimental: first pass at an experimental 4xm demuxer
siretart at users.alioth.debian.org
siretart at users.alioth.debian.org
Sun Jun 30 15:36:24 UTC 2013
The following commit has been merged in the experimental branch:
commit cef4ba9e8a62d0f2d2e8fe5c7b2772abd26b84c9
Author: Mike Melanson <mike at multimedia.cx>
Date: Sun May 25 05:07:36 2003 +0000
first pass at an experimental 4xm demuxer
Originally committed as revision 1903 to svn://svn.ffmpeg.org/ffmpeg/trunk
diff --git a/libavformat/4xm.c b/libavformat/4xm.c
new file mode 100644
index 0000000..b75827f
--- /dev/null
+++ b/libavformat/4xm.c
@@ -0,0 +1,281 @@
+/*
+ * 4X Technologies .4xm File Demuxer (no muxer)
+ * Copyright (c) 2003 The ffmpeg Project
+ *
+ * This library 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 of the License, or (at your option) any later version.
+ *
+ * This library 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 this library; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+/**
+ * @file 4xm.c
+ * 4X Technologies file demuxer
+ * by Mike Melanson (melanson at pcisys.net)
+ * for more information on the .4xm file format, visit:
+ * http://www.pcisys.net/~melanson/codecs/
+ */
+
+#include "avformat.h"
+
+#define LE_16(x) ((((uint8_t*)(x))[1] << 8) | ((uint8_t*)(x))[0])
+#define LE_32(x) ((((uint8_t*)(x))[3] << 24) | \
+ (((uint8_t*)(x))[2] << 16) | \
+ (((uint8_t*)(x))[1] << 8) | \
+ ((uint8_t*)(x))[0])
+#define BE_16(x) ((((uint8_t*)(x))[0] << 8) | ((uint8_t*)(x))[1])
+#define BE_32(x) ((((uint8_t*)(x))[0] << 24) | \
+ (((uint8_t*)(x))[1] << 16) | \
+ (((uint8_t*)(x))[2] << 8) | \
+ ((uint8_t*)(x))[3])
+
+#define FOURCC_TAG( ch0, ch1, ch2, ch3 ) \
+ ( (long)(unsigned char)(ch3) | \
+ ( (long)(unsigned char)(ch2) << 8 ) | \
+ ( (long)(unsigned char)(ch1) << 16 ) | \
+ ( (long)(unsigned char)(ch0) << 24 ) )
+
+#define RIFF_TAG FOURCC_TAG('R', 'I', 'F', 'F')
+#define _4XMV_TAG FOURCC_TAG('4', 'X', 'M', 'V')
+#define LIST_TAG FOURCC_TAG('L', 'I', 'S', 'T')
+#define HEAD_TAG FOURCC_TAG('H', 'E', 'A', 'D')
+#define TRK__TAG FOURCC_TAG('T', 'R', 'K', '_')
+#define MOVI_TAG FOURCC_TAG('M', 'O', 'V', 'I')
+#define VTRK_TAG FOURCC_TAG('V', 'T', 'R', 'K')
+#define STRK_TAG FOURCC_TAG('S', 'T', 'R', 'K')
+#define name_TAG FOURCC_TAG('n', 'a', 'm', 'e')
+#define vtrk_TAG FOURCC_TAG('v', 't', 'r', 'k')
+#define strk_TAG FOURCC_TAG('s', 't', 'r', 'k')
+#define ifrm_TAG FOURCC_TAG('i', 'f', 'r', 'm')
+#define pfrm_TAG FOURCC_TAG('p', 'f', 'r', 'm')
+#define cfrm_TAG FOURCC_TAG('c', 'f', 'r', 'm')
+#define snd__TAG FOURCC_TAG('s', 'n', 'd', '_')
+#define _TAG FOURCC_TAG('', '', '', '')
+
+#define vtrk_SIZE 0x44
+#define strk_SIZE 0x28
+
+#define GET_LIST_HEADER() \
+ fourcc_tag = get_be32(pb); \
+ size = get_le32(pb); \
+ if (fourcc_tag != LIST_TAG) \
+ return AVERROR_INVALIDDATA; \
+ fourcc_tag = get_be32(pb);
+
+typedef struct AudioTrack {
+ int sample_rate;
+ int bits;
+ int channels;
+} AudioTrack;
+
+typedef struct FourxmDemuxContext {
+ int width;
+ int height;
+ int track_count;
+ AudioTrack *tracks;
+ int selected_track;
+} FourxmDemuxContext;
+
+static int fourxm_probe(AVProbeData *p)
+{
+ if ((BE_32(&p->buf[0]) != RIFF_TAG) ||
+ (BE_32(&p->buf[8]) != _4XMV_TAG))
+ return 0;
+
+printf (" detected .4xm file\n");
+
+ return AVPROBE_SCORE_MAX;
+}
+
+static int fourxm_read_header(AVFormatContext *s,
+ AVFormatParameters *ap)
+{
+ ByteIOContext *pb = &s->pb;
+ unsigned int fourcc_tag;
+ unsigned int size;
+ int header_size;
+ FourxmDemuxContext *fourxm = (FourxmDemuxContext *)s->priv_data;
+ unsigned char *header;
+ int i;
+ int current_track = -1;
+ AVStream *st;
+
+ fourxm->track_count = 0;
+ fourxm->tracks = NULL;
+ fourxm->selected_track = 0;
+
+ /* skip the first 3 32-bit numbers */
+ url_fseek(pb, 12, SEEK_CUR);
+
+ /* check for LIST-HEAD */
+ GET_LIST_HEADER();
+ header_size = size - 4;
+ if (fourcc_tag != HEAD_TAG)
+ return AVERROR_INVALIDDATA;
+
+ /* allocate space for the header and load the whole thing */
+ header = av_malloc(header_size);
+ if (!header)
+ return AVERROR_NOMEM;
+ if (get_buffer(pb, header, header_size) != header_size)
+ return AVERROR_IO;
+
+ /* take the lazy approach and search for any and all vtrk and strk chunks */
+ for (i = 0; i < header_size - 8; i++) {
+ fourcc_tag = BE_32(&header[i]);
+ size = LE_32(&header[i + 4]);
+
+ if (fourcc_tag == vtrk_TAG) {
+ /* check that there is enough data */
+ if (size != vtrk_SIZE) {
+ av_free(header);
+ return AVERROR_INVALIDDATA;
+ }
+ fourxm->width = LE_32(&header[i + 36]);
+ fourxm->height = LE_32(&header[i + 40]);
+ i += 8 + size;
+ } else if (fourcc_tag == strk_TAG) {
+ /* check that there is enough data */
+ if (size != strk_SIZE) {
+ av_free(header);
+ return AVERROR_INVALIDDATA;
+ }
+ current_track = LE_32(&header[i + 8]);
+ if (current_track + 1 > fourxm->track_count) {
+ fourxm->track_count++;
+ fourxm->tracks = av_realloc(fourxm->tracks, fourxm->track_count);
+ if (!fourxm->tracks) {
+ av_free(header);
+ return AVERROR_NOMEM;
+ }
+ }
+ fourxm->tracks[current_track].channels = LE_32(&header[i + 36]);
+ fourxm->tracks[current_track].sample_rate = LE_32(&header[i + 40]);
+ fourxm->tracks[current_track].bits = LE_32(&header[i + 44]);
+ i += 8 + size;
+ }
+ }
+
+ av_free(header);
+
+ /* skip over the LIST-MOVI chunk (which is where the stream should be */
+ GET_LIST_HEADER();
+ if (fourcc_tag != MOVI_TAG)
+ return AVERROR_INVALIDDATA;
+
+ if (current_track > -1) {
+ st = av_new_stream(s, 0);
+ if (!st)
+ return AVERROR_NOMEM;
+
+ st->codec.codec_type = CODEC_TYPE_AUDIO;
+ st->codec.codec_tag = 1;
+ st->codec.channels = fourxm->tracks[current_track].channels;
+ st->codec.sample_rate = fourxm->tracks[current_track].sample_rate;
+ st->codec.bits_per_sample = fourxm->tracks[current_track].bits;
+ st->codec.bit_rate = st->codec.channels * st->codec.sample_rate *
+ st->codec.bits_per_sample;
+ st->codec.block_align = st->codec.channels * st->codec.bits_per_sample;
+ if (st->codec.bits_per_sample == 8)
+ st->codec.codec_id = CODEC_ID_PCM_U8;
+ else
+ st->codec.codec_id = CODEC_ID_PCM_S16LE;
+ }
+
+ return 0;
+}
+
+static int fourxm_read_packet(AVFormatContext *s,
+ AVPacket *pkt)
+{
+ FourxmDemuxContext *fourxm = s->priv_data;
+ ByteIOContext *pb = &s->pb;
+ unsigned int fourcc_tag;
+ unsigned int size;
+ int ret = 0;
+ int track_number;
+ int packet_read = 0;
+
+ while (!packet_read) {
+
+ fourcc_tag = get_be32(pb);
+ size = get_le32(pb);
+ if (fourcc_tag == LIST_TAG) {
+ /* skip the LIST-FRAM tag and get the next fourcc */
+ get_be32(pb);
+ fourcc_tag = get_be32(pb);
+ size = get_le32(pb);
+ }
+
+ if (url_feof(pb))
+ return -EIO;
+
+ switch (fourcc_tag) {
+
+ case ifrm_TAG:
+ case pfrm_TAG:
+ case cfrm_TAG:
+printf (" %cfrm chunk\n", (char)(fourcc_tag >> 24) & 0xFF);
+url_fseek(pb, size, SEEK_CUR);
+ break;
+
+ case snd__TAG:
+printf (" snd_ chunk, ");
+ track_number = get_le32(pb);
+ size = get_le32(pb);
+ if (track_number == fourxm->selected_track) {
+printf ("correct track, dispatching...\n");
+ if (av_new_packet(pkt, size))
+ return -EIO;
+ ret = get_buffer(&s->pb, pkt->data, size);
+ if (ret < 0)
+ av_free_packet(pkt);
+ packet_read = 1;
+ } else {
+printf ("wrong track, skipping...\n");
+ url_fseek(pb, size, SEEK_CUR);
+ }
+ break;
+
+ default:
+ url_fseek(pb, size, SEEK_CUR);
+ break;
+ }
+ }
+
+ return ret;
+}
+
+static int fourxm_read_close(AVFormatContext *s)
+{
+ FourxmDemuxContext *fourxm = (FourxmDemuxContext *)s->priv_data;
+
+ av_free(fourxm->tracks);
+
+ return 0;
+}
+
+static AVInputFormat fourxm_iformat = {
+ "4xm",
+ "4X Technologies format",
+ sizeof(FourxmDemuxContext),
+ fourxm_probe,
+ fourxm_read_header,
+ fourxm_read_packet,
+ fourxm_read_close,
+};
+
+int fourxm_init(void)
+{
+ av_register_input_format(&fourxm_iformat);
+ return 0;
+}
diff --git a/libavformat/Makefile b/libavformat/Makefile
index a185e88..670493e 100644
--- a/libavformat/Makefile
+++ b/libavformat/Makefile
@@ -14,7 +14,7 @@ PPOBJS=
# mux and demuxes
OBJS+=mpeg.o mpegts.o ffm.o crc.o img.o raw.o rm.o \
avienc.o avidec.o wav.o swf.o au.o gif.o mov.o mpjpeg.o dv.o \
- yuv4mpeg.o
+ yuv4mpeg.o 4xm.o
ifeq ($(CONFIG_RISKY),yes)
OBJS+= asf.o
--
Libav/FFmpeg packaging
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