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FFmpeg/libavformat/ipmovie.c
Carl Eugen Hoyos 4d8875ec23 lavf: Constify the probe function argument. 
Reviewed-by: Lauri Kasanen
Reviewed-by: Tomas Härdin
2019-03-21 11:42:17 +01:00

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/*
* Interplay MVE File Demuxer
* Copyright (c) 2003 The FFmpeg project
*
* 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
* 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 "libavutil/channel_layout.h"
#include "libavutil/intreadwrite.h"
#include "avformat.h"
#include "internal.h"
#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_VIDEO_DATA_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_SET_SKIP_MAP 0x0E
#define OPCODE_SET_DECODING_MAP 0x0F
#define OPCODE_VIDEO_DATA_10 0x10
#define OPCODE_VIDEO_DATA_11 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 {
AVFormatContext *avf;
unsigned char *buf;
int buf_size;
uint64_t frame_pts_inc;
unsigned int video_bpp;
unsigned int video_width;
unsigned int video_height;
int64_t video_pts;
uint32_t palette[256];
int has_palette;
int changed;
uint8_t send_buffer;
uint8_t frame_format;
unsigned int audio_bits;
unsigned int audio_channels;
unsigned int audio_sample_rate;
enum AVCodecID audio_type;
unsigned int audio_frame_count;
int video_stream_index;
int audio_stream_index;
int64_t audio_chunk_offset;
int audio_chunk_size;
int64_t video_chunk_offset;
int video_chunk_size;
int64_t skip_map_chunk_offset;
int skip_map_chunk_size;
int64_t decode_map_chunk_offset;
int decode_map_chunk_size;
int64_t next_chunk_offset;
} IPMVEContext;
static int load_ipmovie_packet(IPMVEContext *s, AVIOContext *pb,
AVPacket *pkt) {
int chunk_type;
if (s->audio_chunk_offset && s->audio_channels && s->audio_bits) {
if (s->audio_type == AV_CODEC_ID_NONE) {
av_log(s->avf, AV_LOG_ERROR, "Can not read audio packet before"
"audio codec is known\n");
return CHUNK_BAD;
}
/* adjust for PCM audio by skipping chunk header */
if (s->audio_type != AV_CODEC_ID_INTERPLAY_DPCM) {
s->audio_chunk_offset += 6;
s->audio_chunk_size -= 6;
}
avio_seek(pb, s->audio_chunk_offset, SEEK_SET);
s->audio_chunk_offset = 0;
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 = s->audio_frame_count;
/* audio frame maintenance */
if (s->audio_type != AV_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) / s->audio_channels;
av_log(s->avf, AV_LOG_TRACE, "sending audio frame with pts %"PRId64" (%d audio frames)\n",
pkt->pts, s->audio_frame_count);
chunk_type = CHUNK_VIDEO;
} else if (s->frame_format) {
/* send the frame format, decode map, the video data, skip map, and the send_buffer flag together */
if (av_new_packet(pkt, 8 + s->decode_map_chunk_size + s->video_chunk_size + s->skip_map_chunk_size))
return CHUNK_NOMEM;
if (s->has_palette) {
uint8_t *pal;
pal = av_packet_new_side_data(pkt, AV_PKT_DATA_PALETTE,
AVPALETTE_SIZE);
if (pal) {
memcpy(pal, s->palette, AVPALETTE_SIZE);
s->has_palette = 0;
}
}
if (s->changed) {
ff_add_param_change(pkt, 0, 0, 0, s->video_width, s->video_height);
s->changed = 0;
}
AV_WL8(pkt->data, s->frame_format);
AV_WL8(pkt->data + 1, s->send_buffer);
AV_WL16(pkt->data + 2, s->video_chunk_size);
AV_WL16(pkt->data + 4, s->decode_map_chunk_size);
AV_WL16(pkt->data + 6, s->skip_map_chunk_size);
s->frame_format = 0;
s->send_buffer = 0;
pkt->pos = s->video_chunk_offset;
avio_seek(pb, s->video_chunk_offset, SEEK_SET);
s->video_chunk_offset = 0;
if (avio_read(pb, pkt->data + 8, s->video_chunk_size) !=
s->video_chunk_size) {
av_packet_unref(pkt);
return CHUNK_EOF;
}
if (s->decode_map_chunk_size) {
pkt->pos = s->decode_map_chunk_offset;
avio_seek(pb, s->decode_map_chunk_offset, SEEK_SET);
s->decode_map_chunk_offset = 0;
if (avio_read(pb, pkt->data + 8 + s->video_chunk_size,
s->decode_map_chunk_size) != s->decode_map_chunk_size) {
av_packet_unref(pkt);
return CHUNK_EOF;
}
}
if (s->skip_map_chunk_size) {
pkt->pos = s->skip_map_chunk_offset;
avio_seek(pb, s->skip_map_chunk_offset, SEEK_SET);
s->skip_map_chunk_offset = 0;
if (avio_read(pb, pkt->data + 8 + s->video_chunk_size + s->decode_map_chunk_size,
s->skip_map_chunk_size) != s->skip_map_chunk_size) {
av_packet_unref(pkt);
return CHUNK_EOF;
}
}
s->video_chunk_size = 0;
s->decode_map_chunk_size = 0;
s->skip_map_chunk_size = 0;
pkt->stream_index = s->video_stream_index;
pkt->pts = s->video_pts;
av_log(s->avf, AV_LOG_TRACE, "sending video frame with pts %"PRId64"\n", pkt->pts);
s->video_pts += s->frame_pts_inc;
chunk_type = CHUNK_VIDEO;
} else {
avio_seek(pb, s->next_chunk_offset, SEEK_SET);
chunk_type = CHUNK_DONE;
}
return chunk_type;
}
static int init_audio(AVFormatContext *s)
{
IPMVEContext *ipmovie = s->priv_data;
AVStream *st = avformat_new_stream(s, NULL);
if (!st)
return AVERROR(ENOMEM);
avpriv_set_pts_info(st, 32, 1, ipmovie->audio_sample_rate);
ipmovie->audio_stream_index = st->index;
st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
st->codecpar->codec_id = ipmovie->audio_type;
st->codecpar->codec_tag = 0; /* no tag */
st->codecpar->channels = ipmovie->audio_channels;
st->codecpar->channel_layout = st->codecpar->channels == 1 ? AV_CH_LAYOUT_MONO :
AV_CH_LAYOUT_STEREO;
st->codecpar->sample_rate = ipmovie->audio_sample_rate;
st->codecpar->bits_per_coded_sample = ipmovie->audio_bits;
st->codecpar->bit_rate = st->codecpar->channels * st->codecpar->sample_rate *
st->codecpar->bits_per_coded_sample;
if (st->codecpar->codec_id == AV_CODEC_ID_INTERPLAY_DPCM)
st->codecpar->bit_rate /= 2;
st->codecpar->block_align = st->codecpar->channels * st->codecpar->bits_per_coded_sample;
return 0;
}
/* 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, AVIOContext *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;
unsigned int width, height;
/* see if there are any pending packets */
chunk_type = load_ipmovie_packet(s, pb, pkt);
if (chunk_type != CHUNK_DONE)
return chunk_type;
/* read the next chunk, wherever the file happens to be pointing */
if (avio_feof(pb))
return CHUNK_EOF;
if (avio_read(pb, chunk_preamble, CHUNK_PREAMBLE_SIZE) !=
CHUNK_PREAMBLE_SIZE)
return CHUNK_BAD;
chunk_size = AV_RL16(&chunk_preamble[0]);
chunk_type = AV_RL16(&chunk_preamble[2]);
av_log(s->avf, AV_LOG_TRACE, "chunk type 0x%04X, 0x%04X bytes: ", chunk_type, chunk_size);
switch (chunk_type) {
case CHUNK_INIT_AUDIO:
av_log(s->avf, AV_LOG_TRACE, "initialize audio\n");
break;
case CHUNK_AUDIO_ONLY:
av_log(s->avf, AV_LOG_TRACE, "audio only\n");
break;
case CHUNK_INIT_VIDEO:
av_log(s->avf, AV_LOG_TRACE, "initialize video\n");
break;
case CHUNK_VIDEO:
av_log(s->avf, AV_LOG_TRACE, "video (and audio)\n");
break;
case CHUNK_SHUTDOWN:
av_log(s->avf, AV_LOG_TRACE, "shutdown\n");
break;
case CHUNK_END:
av_log(s->avf, AV_LOG_TRACE, "end\n");
break;
default:
av_log(s->avf, AV_LOG_TRACE, "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 (avio_feof(pb)) {
chunk_type = CHUNK_EOF;
break;
}
if (avio_read(pb, opcode_preamble, CHUNK_PREAMBLE_SIZE) !=
CHUNK_PREAMBLE_SIZE) {
chunk_type = CHUNK_BAD;
break;
}
opcode_size = AV_RL16(&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) {
av_log(s->avf, AV_LOG_TRACE, "chunk_size countdown just went negative\n");
chunk_type = CHUNK_BAD;
break;
}
av_log(s->avf, AV_LOG_TRACE, " opcode type %02X, version %d, 0x%04X bytes: ",
opcode_type, opcode_version, opcode_size);
switch (opcode_type) {
case OPCODE_END_OF_STREAM:
av_log(s->avf, AV_LOG_TRACE, "end of stream\n");
avio_skip(pb, opcode_size);
break;
case OPCODE_END_OF_CHUNK:
av_log(s->avf, AV_LOG_TRACE, "end of chunk\n");
avio_skip(pb, opcode_size);
break;
case OPCODE_CREATE_TIMER:
av_log(s->avf, AV_LOG_TRACE, "create timer\n");
if ((opcode_version > 0) || (opcode_size != 6)) {
av_log(s->avf, AV_LOG_TRACE, "bad create_timer opcode\n");
chunk_type = CHUNK_BAD;
break;
}
if (avio_read(pb, scratch, opcode_size) !=
opcode_size) {
chunk_type = CHUNK_BAD;
break;
}
s->frame_pts_inc = ((uint64_t)AV_RL32(&scratch[0])) * AV_RL16(&scratch[4]);
break;
case OPCODE_INIT_AUDIO_BUFFERS:
av_log(s->avf, AV_LOG_TRACE, "initialize audio buffers\n");
if (opcode_version > 1 || opcode_size > 10 || opcode_size < 6) {
av_log(s->avf, AV_LOG_TRACE, "bad init_audio_buffers opcode\n");
chunk_type = CHUNK_BAD;
break;
}
if (avio_read(pb, scratch, opcode_size) !=
opcode_size) {
chunk_type = CHUNK_BAD;
break;
}
s->audio_sample_rate = AV_RL16(&scratch[4]);
audio_flags = AV_RL16(&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 = AV_CODEC_ID_INTERPLAY_DPCM;
else if (s->audio_bits == 16)
s->audio_type = AV_CODEC_ID_PCM_S16LE;
else
s->audio_type = AV_CODEC_ID_PCM_U8;
av_log(s->avf, AV_LOG_TRACE, "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 == AV_CODEC_ID_INTERPLAY_DPCM) ?
"Interplay audio" : "PCM");
break;
case OPCODE_START_STOP_AUDIO:
av_log(s->avf, AV_LOG_TRACE, "start/stop audio\n");
avio_skip(pb, opcode_size);
break;
case OPCODE_INIT_VIDEO_BUFFERS:
av_log(s->avf, AV_LOG_TRACE, "initialize video buffers\n");
if ((opcode_version > 2) || (opcode_size > 8) || opcode_size < 4
|| opcode_version == 2 && opcode_size < 8
) {
av_log(s->avf, AV_LOG_TRACE, "bad init_video_buffers opcode\n");
chunk_type = CHUNK_BAD;
break;
}
if (avio_read(pb, scratch, opcode_size) !=
opcode_size) {
chunk_type = CHUNK_BAD;
break;
}
width = AV_RL16(&scratch[0]) * 8;
height = AV_RL16(&scratch[2]) * 8;
if (width != s->video_width) {
s->video_width = width;
s->changed++;
}
if (height != s->video_height) {
s->video_height = height;
s->changed++;
}
if (opcode_version < 2 || !AV_RL16(&scratch[6])) {
s->video_bpp = 8;
} else {
s->video_bpp = 16;
}
av_log(s->avf, AV_LOG_TRACE, "video resolution: %d x %d\n",
s->video_width, s->video_height);
break;
case OPCODE_UNKNOWN_12:
case OPCODE_UNKNOWN_13:
case OPCODE_UNKNOWN_14:
case OPCODE_UNKNOWN_15:
av_log(s->avf, AV_LOG_TRACE, "unknown (but documented) opcode %02X\n", opcode_type);
avio_skip(pb, opcode_size);
break;
case OPCODE_SEND_BUFFER:
av_log(s->avf, AV_LOG_TRACE, "send buffer\n");
avio_skip(pb, opcode_size);
s->send_buffer = 1;
break;
case OPCODE_AUDIO_FRAME:
av_log(s->avf, AV_LOG_TRACE, "audio frame\n");
/* log position and move on for now */
s->audio_chunk_offset = avio_tell(pb);
s->audio_chunk_size = opcode_size;
avio_skip(pb, opcode_size);
break;
case OPCODE_SILENCE_FRAME:
av_log(s->avf, AV_LOG_TRACE, "silence frame\n");
avio_skip(pb, opcode_size);
break;
case OPCODE_INIT_VIDEO_MODE:
av_log(s->avf, AV_LOG_TRACE, "initialize video mode\n");
avio_skip(pb, opcode_size);
break;
case OPCODE_CREATE_GRADIENT:
av_log(s->avf, AV_LOG_TRACE, "create gradient\n");
avio_skip(pb, opcode_size);
break;
case OPCODE_SET_PALETTE:
av_log(s->avf, AV_LOG_TRACE, "set palette\n");
/* check for the logical maximum palette size
* (3 * 256 + 4 bytes) */
if (opcode_size > 0x304 || opcode_size < 4) {
av_log(s->avf, AV_LOG_TRACE, "demux_ipmovie: set_palette opcode with invalid size\n");
chunk_type = CHUNK_BAD;
break;
}
if (avio_read(pb, scratch, opcode_size) != opcode_size) {
chunk_type = CHUNK_BAD;
break;
}
/* load the palette into internal data structure */
first_color = AV_RL16(&scratch[0]);
last_color = first_color + AV_RL16(&scratch[2]) - 1;
/* sanity check (since they are 16 bit values) */
if ( (first_color > 0xFF) || (last_color > 0xFF)
|| (last_color - first_color + 1)*3 + 4 > opcode_size) {
av_log(s->avf, AV_LOG_TRACE, "demux_ipmovie: set_palette indexes 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[i] = (0xFFU << 24) | (r << 16) | (g << 8) | (b);
s->palette[i] |= s->palette[i] >> 6 & 0x30303;
}
s->has_palette = 1;
break;
case OPCODE_SET_PALETTE_COMPRESSED:
av_log(s->avf, AV_LOG_TRACE, "set palette compressed\n");
avio_skip(pb, opcode_size);
break;
case OPCODE_SET_SKIP_MAP:
av_log(s->avf, AV_LOG_TRACE, "set skip map\n");
/* log position and move on for now */
s->skip_map_chunk_offset = avio_tell(pb);
s->skip_map_chunk_size = opcode_size;
avio_skip(pb, opcode_size);
break;
case OPCODE_SET_DECODING_MAP:
av_log(s->avf, AV_LOG_TRACE, "set decoding map\n");
/* log position and move on for now */
s->decode_map_chunk_offset = avio_tell(pb);
s->decode_map_chunk_size = opcode_size;
avio_skip(pb, opcode_size);
break;
case OPCODE_VIDEO_DATA_06:
av_log(s->avf, AV_LOG_TRACE, "set video data format 0x06\n");
s->frame_format = 0x06;
/* log position and move on for now */
s->video_chunk_offset = avio_tell(pb);
s->video_chunk_size = opcode_size;
avio_skip(pb, opcode_size);
break;
case OPCODE_VIDEO_DATA_10:
av_log(s->avf, AV_LOG_TRACE, "set video data format 0x10\n");
s->frame_format = 0x10;
/* log position and move on for now */
s->video_chunk_offset = avio_tell(pb);
s->video_chunk_size = opcode_size;
avio_skip(pb, opcode_size);
break;
case OPCODE_VIDEO_DATA_11:
av_log(s->avf, AV_LOG_TRACE, "set video data format 0x11\n");
s->frame_format = 0x11;
/* log position and move on for now */
s->video_chunk_offset = avio_tell(pb);
s->video_chunk_size = opcode_size;
avio_skip(pb, opcode_size);
break;
default:
av_log(s->avf, AV_LOG_TRACE, "*** unknown opcode type\n");
chunk_type = CHUNK_BAD;
break;
}
}
if (s->avf->nb_streams == 1 && s->audio_type)
init_audio(s->avf);
/* make a note of where the stream is sitting */
s->next_chunk_offset = avio_tell(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 const char signature[] = "Interplay MVE File\x1A\0\x1A";
static int ipmovie_probe(const AVProbeData *p)
{
const uint8_t *b = p->buf;
const uint8_t *b_end = p->buf + p->buf_size - sizeof(signature);
do {
if (b[0] == signature[0] && memcmp(b, signature, sizeof(signature)) == 0)
return AVPROBE_SCORE_MAX;
b++;
} while (b < b_end);
return 0;
}
static int ipmovie_read_header(AVFormatContext *s)
{
IPMVEContext *ipmovie = s->priv_data;
AVIOContext *pb = s->pb;
AVPacket pkt;
AVStream *st;
unsigned char chunk_preamble[CHUNK_PREAMBLE_SIZE];
int chunk_type, i;
uint8_t signature_buffer[sizeof(signature)];
ipmovie->avf = s;
avio_read(pb, signature_buffer, sizeof(signature_buffer));
while (memcmp(signature_buffer, signature, sizeof(signature))) {
memmove(signature_buffer, signature_buffer + 1, sizeof(signature_buffer) - 1);
signature_buffer[sizeof(signature_buffer) - 1] = avio_r8(pb);
if (avio_feof(pb))
return AVERROR_EOF;
}
/* 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 = ipmovie->skip_map_chunk_offset = 0;
ipmovie->decode_map_chunk_size = ipmovie->video_chunk_size =
ipmovie->skip_map_chunk_size = 0;
ipmovie->send_buffer = ipmovie->frame_format = 0;
/* on the first read, this will position the stream at the first chunk */
ipmovie->next_chunk_offset = avio_tell(pb) + 4;
for (i = 0; i < 256; i++)
ipmovie->palette[i] = 0xFFU << 24;
/* 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 (avio_read(pb, chunk_preamble, CHUNK_PREAMBLE_SIZE) !=
CHUNK_PREAMBLE_SIZE)
return AVERROR(EIO);
chunk_type = AV_RL16(&chunk_preamble[2]);
avio_seek(pb, -CHUNK_PREAMBLE_SIZE, SEEK_CUR);
if (chunk_type == CHUNK_VIDEO)
ipmovie->audio_type = AV_CODEC_ID_NONE; /* no audio */
else if (process_ipmovie_chunk(ipmovie, pb, &pkt) != CHUNK_INIT_AUDIO)
return AVERROR_INVALIDDATA;
/* initialize the stream decoders */
st = avformat_new_stream(s, NULL);
if (!st)
return AVERROR(ENOMEM);
avpriv_set_pts_info(st, 63, 1, 1000000);
ipmovie->video_stream_index = st->index;
st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
st->codecpar->codec_id = AV_CODEC_ID_INTERPLAY_VIDEO;
st->codecpar->codec_tag = 0; /* no fourcc */
st->codecpar->width = ipmovie->video_width;
st->codecpar->height = ipmovie->video_height;
st->codecpar->bits_per_coded_sample = ipmovie->video_bpp;
if (ipmovie->audio_type) {
return init_audio(s);
} else
s->ctx_flags |= AVFMTCTX_NOHEADER;
return 0;
}
static int ipmovie_read_packet(AVFormatContext *s,
AVPacket *pkt)
{
IPMVEContext *ipmovie = s->priv_data;
AVIOContext *pb = s->pb;
int ret;
for (;;) {
ret = process_ipmovie_chunk(ipmovie, pb, pkt);
if (ret == CHUNK_BAD)
ret = AVERROR_INVALIDDATA;
else if (ret == CHUNK_EOF)
ret = AVERROR(EIO);
else if (ret == CHUNK_NOMEM)
ret = AVERROR(ENOMEM);
else if (ret == CHUNK_END || ret == CHUNK_SHUTDOWN)
ret = AVERROR_EOF;
else if (ret == CHUNK_VIDEO)
ret = 0;
else if (ret == CHUNK_INIT_VIDEO || ret == CHUNK_INIT_AUDIO)
continue;
else
continue;
return ret;
}
}
AVInputFormat ff_ipmovie_demuxer = {
.name = "ipmovie",
.long_name = NULL_IF_CONFIG_SMALL("Interplay MVE"),
.priv_data_size = sizeof(IPMVEContext),
.read_probe = ipmovie_probe,
.read_header = ipmovie_read_header,
.read_packet = ipmovie_read_packet,
};
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