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/*
* Microsoft XMV demuxer
* Copyright (c) 2011 Sven Hesse <drmccoy@drmccoy.de>
* Copyright (c) 2011 Matthew Hoops <clone2727@gmail.com>
*
* 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
* Microsoft XMV demuxer
*/
#include <stdint.h>
#include "libavutil/intreadwrite.h"
#include "avformat.h"
#include "internal.h"
#include "riff.h"
#include "libavutil/avassert.h"
/** The min size of an XMV header. */
#define XMV_MIN_HEADER_SIZE 36
/** Audio flag: ADPCM'd 5.1 stream, front left / right channels */
#define XMV_AUDIO_ADPCM51_FRONTLEFTRIGHT 1
/** Audio flag: ADPCM'd 5.1 stream, front center / low frequency channels */
#define XMV_AUDIO_ADPCM51_FRONTCENTERLOW 2
/** Audio flag: ADPCM'd 5.1 stream, rear left / right channels */
#define XMV_AUDIO_ADPCM51_REARLEFTRIGHT 4
/** Audio flag: Any of the ADPCM'd 5.1 stream flags. */
#define XMV_AUDIO_ADPCM51 (XMV_AUDIO_ADPCM51_FRONTLEFTRIGHT | \
XMV_AUDIO_ADPCM51_FRONTCENTERLOW | \
XMV_AUDIO_ADPCM51_REARLEFTRIGHT)
#define XMV_BLOCK_ALIGN_SIZE 36
/** A video packet with an XMV file. */
typedef struct XMVVideoPacket {
int stream_index; ///< The decoder stream index for this video packet.
uint32_t data_size; ///< The size of the remaining video data.
uint64_t data_offset; ///< The offset of the video data within the file.
uint32_t current_frame; ///< The current frame within this video packet.
uint32_t frame_count; ///< The amount of frames within this video packet.
int has_extradata; ///< Does the video packet contain extra data?
uint8_t extradata[4]; ///< The extra data
int64_t last_pts; ///< PTS of the last video frame.
int64_t pts; ///< PTS of the most current video frame.
} XMVVideoPacket;
/** An audio packet with an XMV file. */
typedef struct XMVAudioPacket {
int stream_index; ///< The decoder stream index for this audio packet.
/* Stream format properties. */
uint16_t compression; ///< The type of compression.
uint16_t channels; ///< Number of channels.
uint32_t sample_rate; ///< Sampling rate.
uint16_t bits_per_sample; ///< Bits per compressed sample.
uint32_t bit_rate; ///< Bits of compressed data per second.
uint16_t flags; ///< Flags
unsigned block_align; ///< Bytes per compressed block.
uint16_t block_samples; ///< Decompressed samples per compressed block.
enum AVCodecID codec_id; ///< The codec ID of the compression scheme.
uint32_t data_size; ///< The size of the remaining audio data.
uint64_t data_offset; ///< The offset of the audio data within the file.
uint32_t frame_size; ///< Number of bytes to put into an audio frame.
uint64_t block_count; ///< Running counter of decompressed audio block.
} XMVAudioPacket;
/** Context for demuxing an XMV file. */
typedef struct XMVDemuxContext {
uint16_t audio_track_count; ///< Number of audio track in this file.
uint32_t this_packet_size; ///< Size of the current packet.
uint32_t next_packet_size; ///< Size of the next packet.
uint64_t this_packet_offset; ///< Offset of the current packet.
uint64_t next_packet_offset; ///< Offset of the next packet.
uint16_t current_stream; ///< The index of the stream currently handling.
uint16_t stream_count; ///< The number of streams in this file.
XMVVideoPacket video; ///< The video packet contained in each packet.
XMVAudioPacket *audio; ///< The audio packets contained in each packet.
} XMVDemuxContext;
static int xmv_probe(AVProbeData *p)
{
uint32_t file_version;
if (p->buf_size < XMV_MIN_HEADER_SIZE)
return 0;
file_version = AV_RL32(p->buf + 16);
if ((file_version == 0) || (file_version > 4))
return 0;
if (!memcmp(p->buf + 12, "xobX", 4))
return AVPROBE_SCORE_MAX;
return 0;
}
static int xmv_read_close(AVFormatContext *s)
{
XMVDemuxContext *xmv = s->priv_data;
av_freep(&xmv->audio);
return 0;
}
static int xmv_read_header(AVFormatContext *s)
{
XMVDemuxContext *xmv = s->priv_data;
AVIOContext *pb = s->pb;
AVStream *vst = NULL;
uint32_t file_version;
uint32_t this_packet_size;
uint16_t audio_track;
int ret;
avio_skip(pb, 4); /* Next packet size */
this_packet_size = avio_rl32(pb);
avio_skip(pb, 4); /* Max packet size */
avio_skip(pb, 4); /* "xobX" */
file_version = avio_rl32(pb);
if ((file_version != 4) && (file_version != 2))
avpriv_request_sample(s, "Uncommon version %d", file_version);
/* Video track */
vst = avformat_new_stream(s, NULL);
if (!vst)
return AVERROR(ENOMEM);
avpriv_set_pts_info(vst, 32, 1, 1000);
vst->codec->codec_type = AVMEDIA_TYPE_VIDEO;
vst->codec->codec_id = AV_CODEC_ID_WMV2;
vst->codec->codec_tag = MKBETAG('W', 'M', 'V', '2');
vst->codec->width = avio_rl32(pb);
vst->codec->height = avio_rl32(pb);
vst->duration = avio_rl32(pb);
xmv->video.stream_index = vst->index;
/* Audio tracks */
xmv->audio_track_count = avio_rl16(pb);
avio_skip(pb, 2); /* Unknown (padding?) */
xmv->audio = av_malloc(xmv->audio_track_count * sizeof(XMVAudioPacket));
if (!xmv->audio) {
ret = AVERROR(ENOMEM);
goto fail;
}
for (audio_track = 0; audio_track < xmv->audio_track_count; audio_track++) {
XMVAudioPacket *packet = &xmv->audio[audio_track];
AVStream *ast = NULL;
packet->compression = avio_rl16(pb);
packet->channels = avio_rl16(pb);
packet->sample_rate = avio_rl32(pb);
packet->bits_per_sample = avio_rl16(pb);
packet->flags = avio_rl16(pb);
packet->bit_rate = packet->bits_per_sample *
packet->sample_rate *
packet->channels;
packet->block_align = XMV_BLOCK_ALIGN_SIZE * packet->channels;
packet->block_samples = 64;
packet->codec_id = ff_wav_codec_get_id(packet->compression,
packet->bits_per_sample);
packet->stream_index = -1;
packet->frame_size = 0;
packet->block_count = 0;
/* TODO: ADPCM'd 5.1 sound is encoded in three separate streams.
* Those need to be interleaved to a proper 5.1 stream. */
if (packet->flags & XMV_AUDIO_ADPCM51)
av_log(s, AV_LOG_WARNING, "Unsupported 5.1 ADPCM audio stream "
"(0x%04X)\n", packet->flags);
if (!packet->channels || !packet->sample_rate ||
packet->channels >= UINT16_MAX / XMV_BLOCK_ALIGN_SIZE) {
av_log(s, AV_LOG_ERROR, "Invalid parameters for audio track %d.\n",
audio_track);
ret = AVERROR_INVALIDDATA;
goto fail;
}
ast = avformat_new_stream(s, NULL);
if (!ast) {
ret = AVERROR(ENOMEM);
goto fail;
}
ast->codec->codec_type = AVMEDIA_TYPE_AUDIO;
ast->codec->codec_id = packet->codec_id;
ast->codec->codec_tag = packet->compression;
ast->codec->channels = packet->channels;
ast->codec->sample_rate = packet->sample_rate;
ast->codec->bits_per_coded_sample = packet->bits_per_sample;
ast->codec->bit_rate = packet->bit_rate;
ast->codec->block_align = 36 * packet->channels;
avpriv_set_pts_info(ast, 32, packet->block_samples, packet->sample_rate);
packet->stream_index = ast->index;
ast->duration = vst->duration;
}
/* Initialize the packet context */
xmv->next_packet_offset = avio_tell(pb);
xmv->next_packet_size = this_packet_size - xmv->next_packet_offset;
xmv->stream_count = xmv->audio_track_count + 1;
return 0;
fail:
xmv_read_close(s);
return ret;
}
static void xmv_read_extradata(uint8_t *extradata, AVIOContext *pb)
{
/* Read the XMV extradata */
uint32_t data = avio_rl32(pb);
int mspel_bit = !!(data & 0x01);
int loop_filter = !!(data & 0x02);
int abt_flag = !!(data & 0x04);
int j_type_bit = !!(data & 0x08);
int top_left_mv_flag = !!(data & 0x10);
int per_mb_rl_bit = !!(data & 0x20);
int slice_count = (data >> 6) & 7;
/* Write it back as standard WMV2 extradata */
data = 0;
data |= mspel_bit << 15;
data |= loop_filter << 14;
data |= abt_flag << 13;
data |= j_type_bit << 12;
data |= top_left_mv_flag << 11;
data |= per_mb_rl_bit << 10;
data |= slice_count << 7;
AV_WB32(extradata, data);
}
static int xmv_process_packet_header(AVFormatContext *s)
{
XMVDemuxContext *xmv = s->priv_data;
AVIOContext *pb = s->pb;
uint8_t data[8];
uint16_t audio_track;
uint64_t data_offset;
/* Next packet size */
xmv->next_packet_size = avio_rl32(pb);
/* Packet video header */
if (avio_read(pb, data, 8) != 8)
return AVERROR(EIO);
xmv->video.data_size = AV_RL32(data) & 0x007FFFFF;
xmv->video.current_frame = 0;
xmv->video.frame_count = (AV_RL32(data) >> 23) & 0xFF;
xmv->video.has_extradata = (data[3] & 0x80) != 0;
/* Adding the audio data sizes and the video data size keeps you 4 bytes
* short for every audio track. But as playing around with XMV files with
* ADPCM audio showed, taking the extra 4 bytes from the audio data gives
* you either completely distorted audio or click (when skipping the
* remaining 68 bytes of the ADPCM block). Subtracting 4 bytes for every
* audio track from the video data works at least for the audio. Probably
* some alignment thing?
* The video data has (always?) lots of padding, so it should work out...
*/
xmv->video.data_size -= xmv->audio_track_count * 4;
xmv->current_stream = 0;
if (!xmv->video.frame_count) {
xmv->video.frame_count = 1;
xmv->current_stream = xmv->stream_count > 1;
}
/* Packet audio header */
for (audio_track = 0; audio_track < xmv->audio_track_count; audio_track++) {
XMVAudioPacket *packet = &xmv->audio[audio_track];
if (avio_read(pb, data, 4) != 4)
return AVERROR(EIO);
packet->data_size = AV_RL32(data) & 0x007FFFFF;
if ((packet->data_size == 0) && (audio_track != 0))
/* This happens when I create an XMV with several identical audio
* streams. From the size calculations, duplicating the previous
* stream's size works out, but the track data itself is silent.
* Maybe this should also redirect the offset to the previous track?
*/
packet->data_size = xmv->audio[audio_track - 1].data_size;
/* Carve up the audio data in frame_count slices */
packet->frame_size = packet->data_size / xmv->video.frame_count;
packet->frame_size -= packet->frame_size % packet->block_align;
}
/* Packet data offsets */
data_offset = avio_tell(pb);
xmv->video.data_offset = data_offset;
data_offset += xmv->video.data_size;
for (audio_track = 0; audio_track < xmv->audio_track_count; audio_track++) {
xmv->audio[audio_track].data_offset = data_offset;
data_offset += xmv->audio[audio_track].data_size;
}
/* Video frames header */
/* Read new video extra data */
if (xmv->video.data_size > 0) {
if (xmv->video.has_extradata) {
xmv_read_extradata(xmv->video.extradata, pb);
xmv->video.data_size -= 4;
xmv->video.data_offset += 4;
if (xmv->video.stream_index >= 0) {
AVStream *vst = s->streams[xmv->video.stream_index];
av_assert0(xmv->video.stream_index < s->nb_streams);
if (vst->codec->extradata_size < 4) {
av_free(vst->codec->extradata);
ff_alloc_extradata(vst->codec, 4);
}
memcpy(vst->codec->extradata, xmv->video.extradata, 4);
}
}
}
return 0;
}
static int xmv_fetch_new_packet(AVFormatContext *s)
{
XMVDemuxContext *xmv = s->priv_data;
AVIOContext *pb = s->pb;
int result;
if (xmv->this_packet_offset == xmv->next_packet_offset)
return AVERROR_EOF;
/* Seek to it */
xmv->this_packet_offset = xmv->next_packet_offset;
if (avio_seek(pb, xmv->this_packet_offset, SEEK_SET) != xmv->this_packet_offset)
return AVERROR(EIO);
/* Update the size */
xmv->this_packet_size = xmv->next_packet_size;
if (xmv->this_packet_size < (12 + xmv->audio_track_count * 4))
return AVERROR(EIO);
/* Process the header */
result = xmv_process_packet_header(s);
if (result)
return result;
/* Update the offset */
xmv->next_packet_offset = xmv->this_packet_offset + xmv->this_packet_size;
return 0;
}
static int xmv_fetch_audio_packet(AVFormatContext *s,
AVPacket *pkt, uint32_t stream)
{
XMVDemuxContext *xmv = s->priv_data;
AVIOContext *pb = s->pb;
XMVAudioPacket *audio = &xmv->audio[stream];
uint32_t data_size;
uint32_t block_count;
int result;
/* Seek to it */
if (avio_seek(pb, audio->data_offset, SEEK_SET) != audio->data_offset)
return AVERROR(EIO);
if ((xmv->video.current_frame + 1) < xmv->video.frame_count)
/* Not the last frame, get at most frame_size bytes. */
data_size = FFMIN(audio->frame_size, audio->data_size);
else
/* Last frame, get the rest. */
data_size = audio->data_size;
/* Read the packet */
result = av_get_packet(pb, pkt, data_size);
if (result <= 0)
return result;
pkt->stream_index = audio->stream_index;
/* Calculate the PTS */
block_count = data_size / audio->block_align;
pkt->duration = block_count;
pkt->pts = audio->block_count;
pkt->dts = AV_NOPTS_VALUE;
audio->block_count += block_count;
/* Advance offset */
audio->data_size -= data_size;
audio->data_offset += data_size;
return 0;
}
static int xmv_fetch_video_packet(AVFormatContext *s,
AVPacket *pkt)
{
XMVDemuxContext *xmv = s->priv_data;
AVIOContext *pb = s->pb;
XMVVideoPacket *video = &xmv->video;
int result;
uint32_t frame_header;
uint32_t frame_size, frame_timestamp;
uint8_t *data, *end;
/* Seek to it */
if (avio_seek(pb, video->data_offset, SEEK_SET) != video->data_offset)
return AVERROR(EIO);
/* Read the frame header */
frame_header = avio_rl32(pb);
frame_size = (frame_header & 0x1FFFF) * 4 + 4;
frame_timestamp = (frame_header >> 17);
if ((frame_size + 4) > video->data_size)
return AVERROR(EIO);
/* Get the packet data */
result = av_get_packet(pb, pkt, frame_size);
if (result != frame_size)
return result;
/* Contrary to normal WMV2 video, the bit stream in XMV's
* WMV2 is little-endian.
* TODO: This manual swap is of course suboptimal.
*/
for (data = pkt->data, end = pkt->data + frame_size; data < end; data += 4)
AV_WB32(data, AV_RL32(data));
pkt->stream_index = video->stream_index;
/* Calculate the PTS */
video->last_pts = frame_timestamp + video->pts;
pkt->duration = 0;
pkt->pts = video->last_pts;
pkt->dts = AV_NOPTS_VALUE;
video->pts += frame_timestamp;
/* Keyframe? */
pkt->flags = (pkt->data[0] & 0x80) ? 0 : AV_PKT_FLAG_KEY;
/* Advance offset */
video->data_size -= frame_size + 4;
video->data_offset += frame_size + 4;
return 0;
}
static int xmv_read_packet(AVFormatContext *s,
AVPacket *pkt)
{
XMVDemuxContext *xmv = s->priv_data;
int result;
if (xmv->video.current_frame == xmv->video.frame_count) {
/* No frames left in this packet, so we fetch a new one */
result = xmv_fetch_new_packet(s);
if (result)
return result;
}
if (xmv->current_stream == 0) {
/* Fetch a video frame */
result = xmv_fetch_video_packet(s, pkt);
if (result)
return result;
} else {
/* Fetch an audio frame */
result = xmv_fetch_audio_packet(s, pkt, xmv->current_stream - 1);
if (result)
return result;
}
/* Increase our counters */
if (++xmv->current_stream >= xmv->stream_count) {
xmv->current_stream = 0;
xmv->video.current_frame += 1;
}
return 0;
}
AVInputFormat ff_xmv_demuxer = {
.name = "xmv",
.long_name = NULL_IF_CONFIG_SMALL("Microsoft XMV"),
.priv_data_size = sizeof(XMVDemuxContext),
.read_probe = xmv_probe,
.read_header = xmv_read_header,
.read_packet = xmv_read_packet,
.read_close = xmv_read_close,
};
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