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FFmpeg/libavformat/nuv.c
Mans Rullgard 3383a53e7d lavu: replace int/float punning functions 
The existing functions defined in intfloat_readwrite.[ch] are
both slow and incorrect (infinities are not handled).

This introduces a new header with fast, inline conversion
functions using direct union punning assuming an IEEE-754
system, an assumption already made throughout the code.

The one use of Intel/Motorola extended 80-bit format is
replaced by simpler code sufficient under the present
constraints (positive normal values).

The old functions are marked deprecated and retained for
compatibility.

Signed-off-by: Mans Rullgard <mans@mansr.com>
2011-12-11 18:47:19 +00:00

271 lines
9.1 KiB
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/*
* NuppelVideo demuxer.
* Copyright (c) 2006 Reimar Doeffinger
*
* This file is part of Libav.
*
* Libav 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.
*
* Libav 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 Libav; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "libavutil/intreadwrite.h"
#include "libavutil/intfloat.h"
#include "avformat.h"
#include "internal.h"
#include "riff.h"
typedef struct {
int v_id;
int a_id;
int rtjpg_video;
} NUVContext;
typedef enum {
NUV_VIDEO = 'V',
NUV_EXTRADATA = 'D',
NUV_AUDIO = 'A',
NUV_SEEKP = 'R',
NUV_MYTHEXT = 'X'
} nuv_frametype;
static int nuv_probe(AVProbeData *p) {
if (!memcmp(p->buf, "NuppelVideo", 12))
return AVPROBE_SCORE_MAX;
if (!memcmp(p->buf, "MythTVVideo", 12))
return AVPROBE_SCORE_MAX;
return 0;
}
/// little macro to sanitize packet size
#define PKTSIZE(s) (s & 0xffffff)
/**
* @brief read until we found all data needed for decoding
* @param vst video stream of which to change parameters
* @param ast video stream of which to change parameters
* @param myth set if this is a MythTVVideo format file
* @return 1 if all required codec data was found
*/
static int get_codec_data(AVIOContext *pb, AVStream *vst,
AVStream *ast, int myth) {
nuv_frametype frametype;
if (!vst && !myth)
return 1; // no codec data needed
while (!pb->eof_reached) {
int size, subtype;
frametype = avio_r8(pb);
switch (frametype) {
case NUV_EXTRADATA:
subtype = avio_r8(pb);
avio_skip(pb, 6);
size = PKTSIZE(avio_rl32(pb));
if (vst && subtype == 'R') {
vst->codec->extradata_size = size;
vst->codec->extradata = av_malloc(size);
avio_read(pb, vst->codec->extradata, size);
size = 0;
if (!myth)
return 1;
}
break;
case NUV_MYTHEXT:
avio_skip(pb, 7);
size = PKTSIZE(avio_rl32(pb));
if (size != 128 * 4)
break;
avio_rl32(pb); // version
if (vst) {
vst->codec->codec_tag = avio_rl32(pb);
vst->codec->codec_id =
ff_codec_get_id(ff_codec_bmp_tags, vst->codec->codec_tag);
if (vst->codec->codec_tag == MKTAG('R', 'J', 'P', 'G'))
vst->codec->codec_id = CODEC_ID_NUV;
} else
avio_skip(pb, 4);
if (ast) {
ast->codec->codec_tag = avio_rl32(pb);
ast->codec->sample_rate = avio_rl32(pb);
ast->codec->bits_per_coded_sample = avio_rl32(pb);
ast->codec->channels = avio_rl32(pb);
ast->codec->codec_id =
ff_wav_codec_get_id(ast->codec->codec_tag,
ast->codec->bits_per_coded_sample);
ast->need_parsing = AVSTREAM_PARSE_FULL;
} else
avio_skip(pb, 4 * 4);
size -= 6 * 4;
avio_skip(pb, size);
return 1;
case NUV_SEEKP:
size = 11;
break;
default:
avio_skip(pb, 7);
size = PKTSIZE(avio_rl32(pb));
break;
}
avio_skip(pb, size);
}
return 0;
}
static int nuv_header(AVFormatContext *s, AVFormatParameters *ap) {
NUVContext *ctx = s->priv_data;
AVIOContext *pb = s->pb;
char id_string[12];
double aspect, fps;
int is_mythtv, width, height, v_packs, a_packs;
int stream_nr = 0;
AVStream *vst = NULL, *ast = NULL;
avio_read(pb, id_string, 12);
is_mythtv = !memcmp(id_string, "MythTVVideo", 12);
avio_skip(pb, 5); // version string
avio_skip(pb, 3); // padding
width = avio_rl32(pb);
height = avio_rl32(pb);
avio_rl32(pb); // unused, "desiredwidth"
avio_rl32(pb); // unused, "desiredheight"
avio_r8(pb); // 'P' == progressive, 'I' == interlaced
avio_skip(pb, 3); // padding
aspect = av_int2double(avio_rl64(pb));
if (aspect > 0.9999 && aspect < 1.0001)
aspect = 4.0 / 3.0;
fps = av_int2double(avio_rl64(pb));
// number of packets per stream type, -1 means unknown, e.g. streaming
v_packs = avio_rl32(pb);
a_packs = avio_rl32(pb);
avio_rl32(pb); // text
avio_rl32(pb); // keyframe distance (?)
if (v_packs) {
ctx->v_id = stream_nr++;
vst = avformat_new_stream(s, NULL);
if (!vst)
return AVERROR(ENOMEM);
vst->codec->codec_type = AVMEDIA_TYPE_VIDEO;
vst->codec->codec_id = CODEC_ID_NUV;
vst->codec->width = width;
vst->codec->height = height;
vst->codec->bits_per_coded_sample = 10;
vst->sample_aspect_ratio = av_d2q(aspect * height / width, 10000);
vst->r_frame_rate = av_d2q(fps, 60000);
avpriv_set_pts_info(vst, 32, 1, 1000);
} else
ctx->v_id = -1;
if (a_packs) {
ctx->a_id = stream_nr++;
ast = avformat_new_stream(s, NULL);
if (!ast)
return AVERROR(ENOMEM);
ast->codec->codec_type = AVMEDIA_TYPE_AUDIO;
ast->codec->codec_id = CODEC_ID_PCM_S16LE;
ast->codec->channels = 2;
ast->codec->sample_rate = 44100;
ast->codec->bit_rate = 2 * 2 * 44100 * 8;
ast->codec->block_align = 2 * 2;
ast->codec->bits_per_coded_sample = 16;
avpriv_set_pts_info(ast, 32, 1, 1000);
} else
ctx->a_id = -1;
get_codec_data(pb, vst, ast, is_mythtv);
ctx->rtjpg_video = vst && vst->codec->codec_id == CODEC_ID_NUV;
return 0;
}
#define HDRSIZE 12
static int nuv_packet(AVFormatContext *s, AVPacket *pkt) {
NUVContext *ctx = s->priv_data;
AVIOContext *pb = s->pb;
uint8_t hdr[HDRSIZE];
nuv_frametype frametype;
int ret, size;
while (!pb->eof_reached) {
int copyhdrsize = ctx->rtjpg_video ? HDRSIZE : 0;
uint64_t pos = avio_tell(pb);
ret = avio_read(pb, hdr, HDRSIZE);
if (ret < HDRSIZE)
return ret < 0 ? ret : AVERROR(EIO);
frametype = hdr[0];
size = PKTSIZE(AV_RL32(&hdr[8]));
switch (frametype) {
case NUV_EXTRADATA:
if (!ctx->rtjpg_video) {
avio_skip(pb, size);
break;
}
case NUV_VIDEO:
if (ctx->v_id < 0) {
av_log(s, AV_LOG_ERROR, "Video packet in file without video stream!\n");
avio_skip(pb, size);
break;
}
ret = av_new_packet(pkt, copyhdrsize + size);
if (ret < 0)
return ret;
// HACK: we have no idea if it is a keyframe,
// but if we mark none seeking will not work at all.
pkt->flags |= AV_PKT_FLAG_KEY;
pkt->pos = pos;
pkt->pts = AV_RL32(&hdr[4]);
pkt->stream_index = ctx->v_id;
memcpy(pkt->data, hdr, copyhdrsize);
ret = avio_read(pb, pkt->data + copyhdrsize, size);
if (ret < 0) {
av_free_packet(pkt);
return ret;
}
if (ret < size)
av_shrink_packet(pkt, copyhdrsize + ret);
return 0;
case NUV_AUDIO:
if (ctx->a_id < 0) {
av_log(s, AV_LOG_ERROR, "Audio packet in file without audio stream!\n");
avio_skip(pb, size);
break;
}
ret = av_get_packet(pb, pkt, size);
pkt->flags |= AV_PKT_FLAG_KEY;
pkt->pos = pos;
pkt->pts = AV_RL32(&hdr[4]);
pkt->stream_index = ctx->a_id;
if (ret < 0) return ret;
return 0;
case NUV_SEEKP:
// contains no data, size value is invalid
break;
default:
avio_skip(pb, size);
break;
}
}
return AVERROR(EIO);
}
AVInputFormat ff_nuv_demuxer = {
.name = "nuv",
.long_name = NULL_IF_CONFIG_SMALL("NuppelVideo format"),
.priv_data_size = sizeof(NUVContext),
.read_probe = nuv_probe,
.read_header = nuv_header,
.read_packet = nuv_packet,
.flags = AVFMT_GENERIC_INDEX,
};
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