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|
/*
* Interplay MVE File Demuxer
* 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 ipmovie.c
* Interplay MVE file demuxer
* by Mike Melanson (melanson@pcisys.net)
* For more information regarding the Interplay MVE file format, visit:
* http://www.pcisys.net/~melanson/codecs/
* The aforementioned site also contains a command line utility for parsing
* IP MVE files so that you can get a good idea of the typical structure of
* such files. This demuxer is not the best example to use if you are trying
* to write your own as it uses a rather roundabout approach for splitting
* up and sending out the chunks.
*/
#include "avformat.h"
/* debugging support: #define DEBUG_IPMOVIE as non-zero to see extremely
* verbose information about the demux process */
#define DEBUG_IPMOVIE 0
#if DEBUG_IPMOVIE
#define debug_ipmovie printf
#else
static inline void debug_ipmovie(const char *format, ...) { }
#endif
#define IPMOVIE_SIGNATURE "Interplay MVE File\x1A\0"
#define IPMOVIE_SIGNATURE_SIZE 20
#define CHUNK_PREAMBLE_SIZE 4
#define OPCODE_PREAMBLE_SIZE 4
#define CHUNK_INIT_AUDIO 0x0000
#define CHUNK_AUDIO_ONLY 0x0001
#define CHUNK_INIT_VIDEO 0x0002
#define CHUNK_VIDEO 0x0003
#define CHUNK_SHUTDOWN 0x0004
#define CHUNK_END 0x0005
/* these last types are used internally */
#define CHUNK_DONE 0xFFFC
#define CHUNK_NOMEM 0xFFFD
#define CHUNK_EOF 0xFFFE
#define CHUNK_BAD 0xFFFF
#define OPCODE_END_OF_STREAM 0x00
#define OPCODE_END_OF_CHUNK 0x01
#define OPCODE_CREATE_TIMER 0x02
#define OPCODE_INIT_AUDIO_BUFFERS 0x03
#define OPCODE_START_STOP_AUDIO 0x04
#define OPCODE_INIT_VIDEO_BUFFERS 0x05
#define OPCODE_UNKNOWN_06 0x06
#define OPCODE_SEND_BUFFER 0x07
#define OPCODE_AUDIO_FRAME 0x08
#define OPCODE_SILENCE_FRAME 0x09
#define OPCODE_INIT_VIDEO_MODE 0x0A
#define OPCODE_CREATE_GRADIENT 0x0B
#define OPCODE_SET_PALETTE 0x0C
#define OPCODE_SET_PALETTE_COMPRESSED 0x0D
#define OPCODE_UNKNOWN_0E 0x0E
#define OPCODE_SET_DECODING_MAP 0x0F
#define OPCODE_UNKNOWN_10 0x10
#define OPCODE_VIDEO_DATA 0x11
#define OPCODE_UNKNOWN_12 0x12
#define OPCODE_UNKNOWN_13 0x13
#define OPCODE_UNKNOWN_14 0x14
#define OPCODE_UNKNOWN_15 0x15
#define PALETTE_COUNT 256
typedef struct IPMVEContext {
unsigned char *buf;
int buf_size;
float fps;
int frame_pts_inc;
unsigned int video_width;
unsigned int video_height;
int64_t video_pts;
unsigned int audio_bits;
unsigned int audio_channels;
unsigned int audio_sample_rate;
unsigned int audio_type;
unsigned int audio_frame_count;
int video_stream_index;
int audio_stream_index;
offset_t audio_chunk_offset;
int audio_chunk_size;
offset_t video_chunk_offset;
int video_chunk_size;
offset_t decode_map_chunk_offset;
int decode_map_chunk_size;
offset_t next_chunk_offset;
AVPaletteControl palette_control;
} IPMVEContext;
static int load_ipmovie_packet(IPMVEContext *s, ByteIOContext *pb,
AVPacket *pkt) {
int chunk_type;
int64_t audio_pts = 0;
if (s->audio_chunk_offset) {
/* adjust for PCM audio by skipping chunk header */
if (s->audio_type != CODEC_ID_INTERPLAY_DPCM) {
s->audio_chunk_offset += 6;
s->audio_chunk_size -= 6;
}
url_fseek(pb, s->audio_chunk_offset, SEEK_SET);
s->audio_chunk_offset = 0;
/* figure out the audio pts */
audio_pts = 90000;
audio_pts *= s->audio_frame_count;
audio_pts /= s->audio_sample_rate;
if (s->audio_chunk_size != av_get_packet(pb, pkt, s->audio_chunk_size))
return CHUNK_EOF;
pkt->stream_index = s->audio_stream_index;
pkt->pts = audio_pts;
/* audio frame maintenance */
if (s->audio_type != CODEC_ID_INTERPLAY_DPCM)
s->audio_frame_count +=
(s->audio_chunk_size / s->audio_channels / (s->audio_bits / 8));
else
s->audio_frame_count +=
(s->audio_chunk_size - 6) / s->audio_channels;
debug_ipmovie("sending audio frame with pts %lld (%d audio frames)\n",
audio_pts, s->audio_frame_count);
chunk_type = CHUNK_VIDEO;
} else if (s->decode_map_chunk_offset) {
/* send both the decode map and the video data together */
if (av_new_packet(pkt, s->decode_map_chunk_size + s->video_chunk_size))
return CHUNK_NOMEM;
pkt->pos= s->decode_map_chunk_offset;
url_fseek(pb, s->decode_map_chunk_offset, SEEK_SET);
s->decode_map_chunk_offset = 0;
if (get_buffer(pb, pkt->data, s->decode_map_chunk_size) !=
s->decode_map_chunk_size) {
av_free_packet(pkt);
return CHUNK_EOF;
}
url_fseek(pb, s->video_chunk_offset, SEEK_SET);
s->video_chunk_offset = 0;
if (get_buffer(pb, pkt->data + s->decode_map_chunk_size,
s->video_chunk_size) != s->video_chunk_size) {
av_free_packet(pkt);
return CHUNK_EOF;
}
pkt->stream_index = s->video_stream_index;
pkt->pts = s->video_pts;
debug_ipmovie("sending video frame with pts %lld\n",
pkt->pts);
s->video_pts += s->frame_pts_inc;
chunk_type = CHUNK_VIDEO;
} else {
url_fseek(pb, s->next_chunk_offset, SEEK_SET);
chunk_type = CHUNK_DONE;
}
return chunk_type;
}
/* This function loads and processes a single chunk in an IP movie file.
* It returns the type of chunk that was processed. */
static int process_ipmovie_chunk(IPMVEContext *s, ByteIOContext *pb,
AVPacket *pkt)
{
unsigned char chunk_preamble[CHUNK_PREAMBLE_SIZE];
int chunk_type;
int chunk_size;
unsigned char opcode_preamble[OPCODE_PREAMBLE_SIZE];
unsigned char opcode_type;
unsigned char opcode_version;
int opcode_size;
unsigned char scratch[1024];
int i, j;
int first_color, last_color;
int audio_flags;
unsigned char r, g, b;
/* see if there are any pending packets */
chunk_type = load_ipmovie_packet(s, pb, pkt);
if ((chunk_type == CHUNK_VIDEO) && (chunk_type != CHUNK_DONE))
return chunk_type;
/* read the next chunk, wherever the file happens to be pointing */
if (url_feof(pb))
return CHUNK_EOF;
if (get_buffer(pb, chunk_preamble, CHUNK_PREAMBLE_SIZE) !=
CHUNK_PREAMBLE_SIZE)
return CHUNK_BAD;
chunk_size = LE_16(&chunk_preamble[0]);
chunk_type = LE_16(&chunk_preamble[2]);
debug_ipmovie("chunk type 0x%04X, 0x%04X bytes: ", chunk_type, chunk_size);
switch (chunk_type) {
case CHUNK_INIT_AUDIO:
debug_ipmovie("initialize audio\n");
break;
case CHUNK_AUDIO_ONLY:
debug_ipmovie("audio only\n");
break;
case CHUNK_INIT_VIDEO:
debug_ipmovie("initialize video\n");
break;
case CHUNK_VIDEO:
debug_ipmovie("video (and audio)\n");
break;
case CHUNK_SHUTDOWN:
debug_ipmovie("shutdown\n");
break;
case CHUNK_END:
debug_ipmovie("end\n");
break;
default:
debug_ipmovie("invalid chunk\n");
chunk_type = CHUNK_BAD;
break;
}
while ((chunk_size > 0) && (chunk_type != CHUNK_BAD)) {
/* read the next chunk, wherever the file happens to be pointing */
if (url_feof(pb)) {
chunk_type = CHUNK_EOF;
break;
}
if (get_buffer(pb, opcode_preamble, CHUNK_PREAMBLE_SIZE) !=
CHUNK_PREAMBLE_SIZE) {
chunk_type = CHUNK_BAD;
break;
}
opcode_size = LE_16(&opcode_preamble[0]);
opcode_type = opcode_preamble[2];
opcode_version = opcode_preamble[3];
chunk_size -= OPCODE_PREAMBLE_SIZE;
chunk_size -= opcode_size;
if (chunk_size < 0) {
debug_ipmovie("chunk_size countdown just went negative\n");
chunk_type = CHUNK_BAD;
break;
}
debug_ipmovie(" opcode type %02X, version %d, 0x%04X bytes: ",
opcode_type, opcode_version, opcode_size);
switch (opcode_type) {
case OPCODE_END_OF_STREAM:
debug_ipmovie("end of stream\n");
url_fseek(pb, opcode_size, SEEK_CUR);
break;
case OPCODE_END_OF_CHUNK:
debug_ipmovie("end of chunk\n");
url_fseek(pb, opcode_size, SEEK_CUR);
break;
case OPCODE_CREATE_TIMER:
debug_ipmovie("create timer\n");
if ((opcode_version > 0) || (opcode_size > 6)) {
debug_ipmovie("bad create_timer opcode\n");
chunk_type = CHUNK_BAD;
break;
}
if (get_buffer(pb, scratch, opcode_size) !=
opcode_size) {
chunk_type = CHUNK_BAD;
break;
}
s->fps = 1000000.0 / (LE_32(&scratch[0]) * LE_16(&scratch[4]));
s->frame_pts_inc = 90000 / s->fps;
debug_ipmovie(" %.2f frames/second (timer div = %d, subdiv = %d)\n",
s->fps, LE_32(&scratch[0]), LE_16(&scratch[4]));
break;
case OPCODE_INIT_AUDIO_BUFFERS:
debug_ipmovie("initialize audio buffers\n");
if ((opcode_version > 1) || (opcode_size > 10)) {
debug_ipmovie("bad init_audio_buffers opcode\n");
chunk_type = CHUNK_BAD;
break;
}
if (get_buffer(pb, scratch, opcode_size) !=
opcode_size) {
chunk_type = CHUNK_BAD;
break;
}
s->audio_sample_rate = LE_16(&scratch[4]);
audio_flags = LE_16(&scratch[2]);
/* bit 0 of the flags: 0 = mono, 1 = stereo */
s->audio_channels = (audio_flags & 1) + 1;
/* bit 1 of the flags: 0 = 8 bit, 1 = 16 bit */
s->audio_bits = (((audio_flags >> 1) & 1) + 1) * 8;
/* bit 2 indicates compressed audio in version 1 opcode */
if ((opcode_version == 1) && (audio_flags & 0x4))
s->audio_type = CODEC_ID_INTERPLAY_DPCM;
else if (s->audio_bits == 16)
s->audio_type = CODEC_ID_PCM_S16LE;
else
s->audio_type = CODEC_ID_PCM_U8;
debug_ipmovie("audio: %d bits, %d Hz, %s, %s format\n",
s->audio_bits,
s->audio_sample_rate,
(s->audio_channels == 2) ? "stereo" : "mono",
(s->audio_type == CODEC_ID_INTERPLAY_DPCM) ?
"Interplay audio" : "PCM");
break;
case OPCODE_START_STOP_AUDIO:
debug_ipmovie("start/stop audio\n");
url_fseek(pb, opcode_size, SEEK_CUR);
break;
case OPCODE_INIT_VIDEO_BUFFERS:
debug_ipmovie("initialize video buffers\n");
if ((opcode_version > 2) || (opcode_size > 8)) {
debug_ipmovie("bad init_video_buffers opcode\n");
chunk_type = CHUNK_BAD;
break;
}
if (get_buffer(pb, scratch, opcode_size) !=
opcode_size) {
chunk_type = CHUNK_BAD;
break;
}
s->video_width = LE_16(&scratch[0]) * 8;
s->video_height = LE_16(&scratch[2]) * 8;
debug_ipmovie("video resolution: %d x %d\n",
s->video_width, s->video_height);
break;
case OPCODE_UNKNOWN_06:
case OPCODE_UNKNOWN_0E:
case OPCODE_UNKNOWN_10:
case OPCODE_UNKNOWN_12:
case OPCODE_UNKNOWN_13:
case OPCODE_UNKNOWN_14:
case OPCODE_UNKNOWN_15:
debug_ipmovie("unknown (but documented) opcode %02X\n", opcode_type);
url_fseek(pb, opcode_size, SEEK_CUR);
break;
case OPCODE_SEND_BUFFER:
debug_ipmovie("send buffer\n");
url_fseek(pb, opcode_size, SEEK_CUR);
break;
case OPCODE_AUDIO_FRAME:
debug_ipmovie("audio frame\n");
/* log position and move on for now */
s->audio_chunk_offset = url_ftell(pb);
s->audio_chunk_size = opcode_size;
url_fseek(pb, opcode_size, SEEK_CUR);
break;
case OPCODE_SILENCE_FRAME:
debug_ipmovie("silence frame\n");
url_fseek(pb, opcode_size, SEEK_CUR);
break;
case OPCODE_INIT_VIDEO_MODE:
debug_ipmovie("initialize video mode\n");
url_fseek(pb, opcode_size, SEEK_CUR);
break;
case OPCODE_CREATE_GRADIENT:
debug_ipmovie("create gradient\n");
url_fseek(pb, opcode_size, SEEK_CUR);
break;
case OPCODE_SET_PALETTE:
debug_ipmovie("set palette\n");
/* check for the logical maximum palette size
* (3 * 256 + 4 bytes) */
if (opcode_size > 0x304) {
debug_ipmovie("demux_ipmovie: set_palette opcode too large\n");
chunk_type = CHUNK_BAD;
break;
}
if (get_buffer(pb, scratch, opcode_size) != opcode_size) {
chunk_type = CHUNK_BAD;
break;
}
/* load the palette into internal data structure */
first_color = LE_16(&scratch[0]);
last_color = first_color + LE_16(&scratch[2]) - 1;
/* sanity check (since they are 16 bit values) */
if ((first_color > 0xFF) || (last_color > 0xFF)) {
debug_ipmovie("demux_ipmovie: set_palette indices out of range (%d -> %d)\n",
first_color, last_color);
chunk_type = CHUNK_BAD;
break;
}
j = 4; /* offset of first palette data */
for (i = first_color; i <= last_color; i++) {
/* the palette is stored as a 6-bit VGA palette, thus each
* component is shifted up to a 8-bit range */
r = scratch[j++] * 4;
g = scratch[j++] * 4;
b = scratch[j++] * 4;
s->palette_control.palette[i] = (r << 16) | (g << 8) | (b);
}
/* indicate a palette change */
s->palette_control.palette_changed = 1;
break;
case OPCODE_SET_PALETTE_COMPRESSED:
debug_ipmovie("set palette compressed\n");
url_fseek(pb, opcode_size, SEEK_CUR);
break;
case OPCODE_SET_DECODING_MAP:
debug_ipmovie("set decoding map\n");
/* log position and move on for now */
s->decode_map_chunk_offset = url_ftell(pb);
s->decode_map_chunk_size = opcode_size;
url_fseek(pb, opcode_size, SEEK_CUR);
break;
case OPCODE_VIDEO_DATA:
debug_ipmovie("set video data\n");
/* log position and move on for now */
s->video_chunk_offset = url_ftell(pb);
s->video_chunk_size = opcode_size;
url_fseek(pb, opcode_size, SEEK_CUR);
break;
default:
debug_ipmovie("*** unknown opcode type\n");
chunk_type = CHUNK_BAD;
break;
}
}
/* make a note of where the stream is sitting */
s->next_chunk_offset = url_ftell(pb);
/* dispatch the first of any pending packets */
if ((chunk_type == CHUNK_VIDEO) || (chunk_type == CHUNK_AUDIO_ONLY))
chunk_type = load_ipmovie_packet(s, pb, pkt);
return chunk_type;
}
static int ipmovie_probe(AVProbeData *p)
{
if (p->buf_size < IPMOVIE_SIGNATURE_SIZE)
return 0;
if (strncmp(p->buf, IPMOVIE_SIGNATURE, IPMOVIE_SIGNATURE_SIZE) != 0)
return 0;
return AVPROBE_SCORE_MAX;
}
static int ipmovie_read_header(AVFormatContext *s,
AVFormatParameters *ap)
{
IPMVEContext *ipmovie = (IPMVEContext *)s->priv_data;
ByteIOContext *pb = &s->pb;
AVPacket pkt;
AVStream *st;
unsigned char chunk_preamble[CHUNK_PREAMBLE_SIZE];
int chunk_type;
/* initialize private context members */
ipmovie->video_pts = ipmovie->audio_frame_count = 0;
ipmovie->audio_chunk_offset = ipmovie->video_chunk_offset =
ipmovie->decode_map_chunk_offset = 0;
/* on the first read, this will position the stream at the first chunk */
ipmovie->next_chunk_offset = IPMOVIE_SIGNATURE_SIZE + 6;
/* process the first chunk which should be CHUNK_INIT_VIDEO */
if (process_ipmovie_chunk(ipmovie, pb, &pkt) != CHUNK_INIT_VIDEO)
return AVERROR_INVALIDDATA;
/* peek ahead to the next chunk-- if it is an init audio chunk, process
* it; if it is the first video chunk, this is a silent file */
if (get_buffer(pb, chunk_preamble, CHUNK_PREAMBLE_SIZE) !=
CHUNK_PREAMBLE_SIZE)
return AVERROR_IO;
chunk_type = LE_16(&chunk_preamble[2]);
url_fseek(pb, -CHUNK_PREAMBLE_SIZE, SEEK_CUR);
if (chunk_type == CHUNK_VIDEO)
ipmovie->audio_type = 0; /* no audio */
else if (process_ipmovie_chunk(ipmovie, pb, &pkt) != CHUNK_INIT_AUDIO)
return AVERROR_INVALIDDATA;
/* initialize the stream decoders */
st = av_new_stream(s, 0);
if (!st)
return AVERROR_NOMEM;
av_set_pts_info(st, 33, 1, 90000);
ipmovie->video_stream_index = st->index;
st->codec.codec_type = CODEC_TYPE_VIDEO;
st->codec.codec_id = CODEC_ID_INTERPLAY_VIDEO;
st->codec.codec_tag = 0; /* no fourcc */
st->codec.width = ipmovie->video_width;
st->codec.height = ipmovie->video_height;
/* palette considerations */
st->codec.palctrl = &ipmovie->palette_control;
if (ipmovie->audio_type) {
st = av_new_stream(s, 0);
if (!st)
return AVERROR_NOMEM;
av_set_pts_info(st, 33, 1, 90000);
ipmovie->audio_stream_index = st->index;
st->codec.codec_type = CODEC_TYPE_AUDIO;
st->codec.codec_id = ipmovie->audio_type;
st->codec.codec_tag = 0; /* no tag */
st->codec.channels = ipmovie->audio_channels;
st->codec.sample_rate = ipmovie->audio_sample_rate;
st->codec.bits_per_sample = ipmovie->audio_bits;
st->codec.bit_rate = st->codec.channels * st->codec.sample_rate *
st->codec.bits_per_sample;
if (st->codec.codec_id == CODEC_ID_INTERPLAY_DPCM)
st->codec.bit_rate /= 2;
st->codec.block_align = st->codec.channels * st->codec.bits_per_sample;
}
return 0;
}
static int ipmovie_read_packet(AVFormatContext *s,
AVPacket *pkt)
{
IPMVEContext *ipmovie = (IPMVEContext *)s->priv_data;
ByteIOContext *pb = &s->pb;
int ret;
ret = process_ipmovie_chunk(ipmovie, pb, pkt);
if (ret == CHUNK_BAD)
ret = AVERROR_INVALIDDATA;
else if (ret == CHUNK_EOF)
ret = AVERROR_IO;
else if (ret == CHUNK_NOMEM)
ret = AVERROR_NOMEM;
else
ret = 0;
return ret;
}
static int ipmovie_read_close(AVFormatContext *s)
{
// IPMVEContext *ipmovie = (IPMVEContext *)s->priv_data;
return 0;
}
static AVInputFormat ipmovie_iformat = {
"ipmovie",
"Interplay MVE format",
sizeof(IPMVEContext),
ipmovie_probe,
ipmovie_read_header,
ipmovie_read_packet,
ipmovie_read_close,
};
int ipmovie_init(void)
{
av_register_input_format(&ipmovie_iformat);
return 0;
}
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