--- /dev/null
+/*
+ * 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 "riff.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)
+
+/** 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
+ uint16_t block_align; ///< Bytes per compressed block.
+ uint16_t block_samples; ///< Decompressed samples per compressed block.
+
+ enum CodecID 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_header(AVFormatContext *s,
+ AVFormatParameters *ap)
+{
+ 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;
+
+ 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))
+ av_log_ask_for_sample(s, "Found uncommon version %d\n", file_version);
+
+
+ /* Video track */
+
+ vst = av_new_stream(s, 0);
+ if (!vst)
+ return AVERROR(ENOMEM);
+
+ av_set_pts_info(vst, 32, 1, 1000);
+
+ vst->codec->codec_type = AVMEDIA_TYPE_VIDEO;
+ vst->codec->codec_id = 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)
+ return AVERROR(ENOMEM);
+
+ 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 = 36 * 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);
+
+ ast = av_new_stream(s, audio_track);
+ if (!ast)
+ return AVERROR(ENOMEM);
+
+ 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;
+
+ av_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;
+}
+
+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). Substracting 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 = 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];
+
+ assert(xmv->video.stream_index < s->nb_streams);
+
+ if (vst->codec->extradata_size < 4) {
+ av_free(vst->codec->extradata);
+
+ vst->codec->extradata =
+ av_malloc(4 + FF_INPUT_BUFFER_PADDING_SIZE);
+ vst->codec->extradata_size = 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;
+
+ /* 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;
+}
+
+static int xmv_read_close(AVFormatContext *s)
+{
+ XMVDemuxContext *xmv = s->priv_data;
+
+ av_free(xmv->audio);
+
+ 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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