libavformat/moflex.c - manifest_repos/ffmpeg - Git at Google

 /*
  * MOFLEX demuxer
  * Copyright (c) 2020 Paul B Mahol
  *
  * 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
  */

 #include "libavcodec/bytestream.h"

 #include "avformat.h"
 #include "internal.h"

 typedef struct BitReader {
     unsigned last;
     unsigned pos;
 } BitReader;

 typedef struct MOFLEXDemuxContext {
     unsigned size;
     int64_t pos;
     int64_t ts;
     int flags;
     int in_block;

     BitReader br;
 } MOFLEXDemuxContext;

 static int pop(BitReader *br, AVIOContext *pb)
 {
     if (avio_feof(pb))
         return AVERROR_EOF;

     if ((br->pos & 7) == 0)
         br->last = (unsigned)avio_r8(pb) << 24U;
     else
         br->last <<= 1;

     br->pos++;
     return !!(br->last & 0x80000000);
 }

 static int pop_int(BitReader *br, AVIOContext *pb, int n)
 {
     int value = 0;

     for (int i = 0; i < n; i++) {
         int ret = pop(br, pb);

         if (ret < 0)
             return ret;
         if (ret > INT_MAX - value - value)
             return AVERROR_INVALIDDATA;
         value = 2 * value + ret;
     }

     return value;
 }

 static int pop_length(BitReader *br, AVIOContext *pb)
 {
     int ret, n = 1;

     while ((ret = pop(br, pb)) == 0)
         n++;

     if (ret < 0)
         return ret;
     return n;
 }

 static int read_var_byte(AVFormatContext *s, unsigned *out)
 {
     AVIOContext *pb = s->pb;
     unsigned value = 0, data;

     data = avio_r8(pb);
     if (!(data & 0x80)) {
         *out = data;
         return 0;
     }

     value = (data & 0x7F) << 7;
     data = avio_r8(pb);
     if (!(data & 0x80)) {
         value |= data;
         *out = value;
         return 0;
     }

     value = ((data & 0x7F) | value) << 7;
     data = avio_r8(pb);
     if (!(data & 0x80)) {
         value |= data;
         *out = value;
         return 0;
     }

     value = (((data & 0x7F) | value) << 7) | avio_r8(pb);
     *out = value;

     return 0;
 }

 static int moflex_probe(const AVProbeData *p)
 {
     GetByteContext gb;
     int score = 0;

     bytestream2_init(&gb, p->buf, p->buf_size);

     if (bytestream2_get_be16(&gb) != 0x4C32)
         return 0;
     score += 10;

     bytestream2_skip(&gb, 10);
     if (bytestream2_get_be16(&gb) == 0)
         return 0;
     score += 5;

     while (bytestream2_get_bytes_left(&gb) > 0) {
         int type = bytestream2_get_byte(&gb);
         int size = bytestream2_get_byte(&gb);

         if (type == 0) {
             score += 5 * (size == 0);
             break;
         }
         if ((type == 1 && size == 12) ||
             (type == 2 && size ==  6) ||
             (type == 3 && size == 13) ||
             (type == 4 && size ==  2))
             score += 20;
         bytestream2_skip(&gb, size);
     }

     return FFMIN(AVPROBE_SCORE_MAX, score);
 }

 static int moflex_read_sync(AVFormatContext *s)
 {
     MOFLEXDemuxContext *m = s->priv_data;
     AVIOContext *pb = s->pb;

     if (avio_rb16(pb) != 0x4C32) {
         if (avio_feof(pb))
             return AVERROR_EOF;
         avio_seek(pb, -2, SEEK_CUR);
         return 1;
     }

     avio_skip(pb, 2);
     m->ts = avio_rb64(pb);
     m->size = avio_rb16(pb) + 1;

     while (!avio_feof(pb)) {
         unsigned type, ssize, codec_id = 0;
         unsigned codec_type, width = 0, height = 0, sample_rate = 0, channels = 0;
         int stream_index = -1;
         int format;
         AVRational fps;

         read_var_byte(s, &type);
         read_var_byte(s, &ssize);

         switch (type) {
         case 0:
             if (ssize > 0)
                 avio_skip(pb, ssize);
             return 0;
         case 2:
             codec_type = AVMEDIA_TYPE_AUDIO;
             stream_index = avio_r8(pb);
             codec_id = avio_r8(pb);
             switch (codec_id) {
             case 0: codec_id = AV_CODEC_ID_FASTAUDIO; break;
             case 1: codec_id = AV_CODEC_ID_ADPCM_IMA_MOFLEX; break;
             case 2: codec_id = AV_CODEC_ID_PCM_S16LE; break;
             default:
                 av_log(s, AV_LOG_ERROR, "Unsupported audio codec: %d\n", codec_id);
                 return AVERROR_PATCHWELCOME;
             }
             sample_rate = avio_rb24(pb) + 1;
             channels = avio_r8(pb) + 1;
             break;
         case 1:
         case 3:
             codec_type = AVMEDIA_TYPE_VIDEO;
             stream_index = avio_r8(pb);
             codec_id = avio_r8(pb);
             switch (codec_id) {
             case 0: codec_id = AV_CODEC_ID_MOBICLIP; break;
             default:
                 av_log(s, AV_LOG_ERROR, "Unsupported video codec: %d\n", codec_id);
                 return AVERROR_PATCHWELCOME;
             }
             fps.num = avio_rb16(pb);
             fps.den = avio_rb16(pb);
             width = avio_rb16(pb);
             height = avio_rb16(pb);
             format = AV_PIX_FMT_YUV420P;
             avio_skip(pb, type == 3 ? 3 : 2);
             break;
         case 4:
             codec_type = AVMEDIA_TYPE_DATA;
             stream_index = avio_r8(pb);
             avio_skip(pb, 1);
             break;
         }

         if (stream_index == s->nb_streams) {
             AVStream *st = avformat_new_stream(s, NULL);

             if (!st)
                 return AVERROR(ENOMEM);

             st->codecpar->codec_type = codec_type;
             st->codecpar->codec_id   = codec_id;
             st->codecpar->width      = width;
             st->codecpar->height     = height;
             st->codecpar->sample_rate= sample_rate;
             st->codecpar->channels   = channels;
             st->codecpar->format     = format;
             st->priv_data            = av_packet_alloc();
             if (!st->priv_data)
                 return AVERROR(ENOMEM);

             if (sample_rate)
                 avpriv_set_pts_info(st, 63, 1, sample_rate);
             else
                 avpriv_set_pts_info(st, 63, fps.den, fps.num);
         }
     }

     return 0;
 }

 static int moflex_read_header(AVFormatContext *s)
 {
     int ret;

     ret = moflex_read_sync(s);
     if (ret < 0)
         return ret;

     s->ctx_flags |= AVFMTCTX_NOHEADER;
     avio_seek(s->pb, 0, SEEK_SET);

     return 0;
 }

 static int moflex_read_packet(AVFormatContext *s, AVPacket *pkt)
 {
     MOFLEXDemuxContext *m = s->priv_data;
     AVIOContext *pb = s->pb;
     BitReader *br = &m->br;
     int ret;

     while (!avio_feof(pb)) {
         if (!m->in_block) {
             m->pos = avio_tell(pb);

             ret = moflex_read_sync(s);
             if (ret < 0)
                 return ret;

             m->flags = avio_r8(pb);
             if (m->flags & 2)
                 avio_skip(pb, 2);
         }

         while ((avio_tell(pb) < m->pos + m->size) && !avio_feof(pb) && avio_r8(pb)) {
             int stream_index, bits, pkt_size, endframe;
             AVPacket *packet;

             m->in_block = 1;

             avio_seek(pb, -1, SEEK_CUR);
             br->pos = br->last = 0;

             bits = pop_length(br, pb);
             if (bits < 0)
                 return bits;
             stream_index = pop_int(br, pb, bits);
             if (stream_index < 0)
                 return stream_index;
             if (stream_index >= s->nb_streams)
                 return AVERROR_INVALIDDATA;

             endframe = pop(br, pb);
             if (endframe < 0)
                 return endframe;
             if (endframe) {
                 bits = pop_length(br, pb);
                 if (bits < 0)
                     return bits;
                 pop_int(br, pb, bits);
                 pop(br, pb);
                 bits = pop_length(br, pb);
                 if (bits < 0)
                     return bits;
                 pop_int(br, pb, bits * 2 + 26);
             }

             pkt_size = pop_int(br, pb, 13) + 1;
             if (pkt_size > m->size)
                 return AVERROR_INVALIDDATA;
             packet   = s->streams[stream_index]->priv_data;
             if (!packet) {
                 avio_skip(pb, pkt_size);
                 continue;
             }

             ret = av_append_packet(pb, packet, pkt_size);
             if (ret < 0)
                 return ret;
             if (endframe && packet->size > 0) {
                 av_packet_move_ref(pkt, packet);
                 pkt->pos = m->pos;
                 pkt->stream_index = stream_index;
                 if (s->streams[stream_index]->codecpar->codec_type == AVMEDIA_TYPE_VIDEO) {
                     pkt->duration = 1;
                     if (pkt->data[0] & 0x80)
                         pkt->flags |= AV_PKT_FLAG_KEY;
                 } else {
                     pkt->flags |= AV_PKT_FLAG_KEY;
                 }
                 return ret;
             }
         }

         m->in_block = 0;

         if (m->flags % 2 == 0) {
             if (m->size <= 0)
                 return AVERROR_INVALIDDATA;
             avio_seek(pb, m->pos + m->size, SEEK_SET);
         }
     }

     return AVERROR_EOF;
 }

 static int moflex_read_seek(AVFormatContext *s, int stream_index,
                             int64_t pts, int flags)
 {
     MOFLEXDemuxContext *m = s->priv_data;

     m->in_block = 0;

     return -1;
 }

 static int moflex_read_close(AVFormatContext *s)
 {
     for (int i = 0; i < s->nb_streams; i++) {
         AVPacket *packet = s->streams[i]->priv_data;

         av_packet_free(&packet);
         s->streams[i]->priv_data = 0;
     }

     return 0;
 }

 AVInputFormat ff_moflex_demuxer = {
     .name           = "moflex",
     .long_name      = NULL_IF_CONFIG_SMALL("MobiClip MOFLEX"),
     .priv_data_size = sizeof(MOFLEXDemuxContext),
     .read_probe     = moflex_probe,
     .read_header    = moflex_read_header,
     .read_packet    = moflex_read_packet,
     .read_seek      = moflex_read_seek,
     .read_close     = moflex_read_close,
     .extensions     = "moflex",
     .flags          = AVFMT_GENERIC_INDEX,
 };
	/*
	* MOFLEX demuxer
	* Copyright (c) 2020 Paul B Mahol
	*
	* 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
	*/

	#include "libavcodec/bytestream.h"

	#include "avformat.h"
	#include "internal.h"

	typedef struct BitReader {
	unsigned last;
	unsigned pos;
	} BitReader;

	typedef struct MOFLEXDemuxContext {
	unsigned size;
	int64_t pos;
	int64_t ts;
	int flags;
	int in_block;

	BitReader br;
	} MOFLEXDemuxContext;

	static int pop(BitReader br, AVIOContext pb)
	{
	if (avio_feof(pb))
	return AVERROR_EOF;

	if ((br->pos & 7) == 0)
	br->last = (unsigned)avio_r8(pb) << 24U;
	else
	br->last <<= 1;

	br->pos++;
	return !!(br->last & 0x80000000);
	}

	static int pop_int(BitReader br, AVIOContext pb, int n)
	{
	int value = 0;

	for (int i = 0; i < n; i++) {
	int ret = pop(br, pb);

	if (ret < 0)
	return ret;
	if (ret > INT_MAX - value - value)
	return AVERROR_INVALIDDATA;
	value = 2 * value + ret;
	}

	return value;
	}

	static int pop_length(BitReader br, AVIOContext pb)
	{
	int ret, n = 1;

	while ((ret = pop(br, pb)) == 0)
	n++;

	if (ret < 0)
	return ret;
	return n;
	}

	static int read_var_byte(AVFormatContext s, unsigned out)
	{
	AVIOContext *pb = s->pb;
	unsigned value = 0, data;

	data = avio_r8(pb);
	if (!(data & 0x80)) {
	*out = data;
	return 0;
	}

	value = (data & 0x7F) << 7;
	data = avio_r8(pb);
	if (!(data & 0x80)) {
	value \|= data;
	*out = value;
	return 0;
	}

	value = ((data & 0x7F) \| value) << 7;
	data = avio_r8(pb);
	if (!(data & 0x80)) {
	value \|= data;
	*out = value;
	return 0;
	}

	value = (((data & 0x7F) \| value) << 7) \| avio_r8(pb);
	*out = value;

	return 0;
	}

	static int moflex_probe(const AVProbeData *p)
	{
	GetByteContext gb;
	int score = 0;

	bytestream2_init(&gb, p->buf, p->buf_size);

	if (bytestream2_get_be16(&gb) != 0x4C32)
	return 0;
	score += 10;

	bytestream2_skip(&gb, 10);
	if (bytestream2_get_be16(&gb) == 0)
	return 0;
	score += 5;

	while (bytestream2_get_bytes_left(&gb) > 0) {
	int type = bytestream2_get_byte(&gb);
	int size = bytestream2_get_byte(&gb);

	if (type == 0) {
	score += 5 * (size == 0);
	break;
	}
	if ((type == 1 && size == 12) \|\|
	(type == 2 && size == 6) \|\|
	(type == 3 && size == 13) \|\|
	(type == 4 && size == 2))
	score += 20;
	bytestream2_skip(&gb, size);
	}

	return FFMIN(AVPROBE_SCORE_MAX, score);
	}

	static int moflex_read_sync(AVFormatContext *s)
	{
	MOFLEXDemuxContext *m = s->priv_data;
	AVIOContext *pb = s->pb;

	if (avio_rb16(pb) != 0x4C32) {
	if (avio_feof(pb))
	return AVERROR_EOF;
	avio_seek(pb, -2, SEEK_CUR);
	return 1;
	}

	avio_skip(pb, 2);
	m->ts = avio_rb64(pb);
	m->size = avio_rb16(pb) + 1;

	while (!avio_feof(pb)) {
	unsigned type, ssize, codec_id = 0;
	unsigned codec_type, width = 0, height = 0, sample_rate = 0, channels = 0;
	int stream_index = -1;
	int format;
	AVRational fps;

	read_var_byte(s, &type);
	read_var_byte(s, &ssize);

	switch (type) {
	case 0:
	if (ssize > 0)
	avio_skip(pb, ssize);
	return 0;
	case 2:
	codec_type = AVMEDIA_TYPE_AUDIO;
	stream_index = avio_r8(pb);
	codec_id = avio_r8(pb);
	switch (codec_id) {
	case 0: codec_id = AV_CODEC_ID_FASTAUDIO; break;
	case 1: codec_id = AV_CODEC_ID_ADPCM_IMA_MOFLEX; break;
	case 2: codec_id = AV_CODEC_ID_PCM_S16LE; break;
	default:
	av_log(s, AV_LOG_ERROR, "Unsupported audio codec: %d\n", codec_id);
	return AVERROR_PATCHWELCOME;
	}
	sample_rate = avio_rb24(pb) + 1;
	channels = avio_r8(pb) + 1;
	break;
	case 1:
	case 3:
	codec_type = AVMEDIA_TYPE_VIDEO;
	stream_index = avio_r8(pb);
	codec_id = avio_r8(pb);
	switch (codec_id) {
	case 0: codec_id = AV_CODEC_ID_MOBICLIP; break;
	default:
	av_log(s, AV_LOG_ERROR, "Unsupported video codec: %d\n", codec_id);
	return AVERROR_PATCHWELCOME;
	}
	fps.num = avio_rb16(pb);
	fps.den = avio_rb16(pb);
	width = avio_rb16(pb);
	height = avio_rb16(pb);
	format = AV_PIX_FMT_YUV420P;
	avio_skip(pb, type == 3 ? 3 : 2);
	break;
	case 4:
	codec_type = AVMEDIA_TYPE_DATA;
	stream_index = avio_r8(pb);
	avio_skip(pb, 1);
	break;
	}

	if (stream_index == s->nb_streams) {
	AVStream *st = avformat_new_stream(s, NULL);

	if (!st)
	return AVERROR(ENOMEM);

	st->codecpar->codec_type = codec_type;
	st->codecpar->codec_id = codec_id;
	st->codecpar->width = width;
	st->codecpar->height = height;
	st->codecpar->sample_rate= sample_rate;
	st->codecpar->channels = channels;
	st->codecpar->format = format;
	st->priv_data = av_packet_alloc();
	if (!st->priv_data)
	return AVERROR(ENOMEM);

	if (sample_rate)
	avpriv_set_pts_info(st, 63, 1, sample_rate);
	else
	avpriv_set_pts_info(st, 63, fps.den, fps.num);
	}
	}

	return 0;
	}

	static int moflex_read_header(AVFormatContext *s)
	{
	int ret;

	ret = moflex_read_sync(s);
	if (ret < 0)
	return ret;

	s->ctx_flags \|= AVFMTCTX_NOHEADER;
	avio_seek(s->pb, 0, SEEK_SET);

	return 0;
	}

	static int moflex_read_packet(AVFormatContext s, AVPacket pkt)
	{
	MOFLEXDemuxContext *m = s->priv_data;
	AVIOContext *pb = s->pb;
	BitReader *br = &m->br;
	int ret;

	while (!avio_feof(pb)) {
	if (!m->in_block) {
	m->pos = avio_tell(pb);

	ret = moflex_read_sync(s);
	if (ret < 0)
	return ret;

	m->flags = avio_r8(pb);
	if (m->flags & 2)
	avio_skip(pb, 2);
	}

	while ((avio_tell(pb) < m->pos + m->size) && !avio_feof(pb) && avio_r8(pb)) {
	int stream_index, bits, pkt_size, endframe;
	AVPacket *packet;

	m->in_block = 1;

	avio_seek(pb, -1, SEEK_CUR);
	br->pos = br->last = 0;

	bits = pop_length(br, pb);
	if (bits < 0)
	return bits;
	stream_index = pop_int(br, pb, bits);
	if (stream_index < 0)
	return stream_index;
	if (stream_index >= s->nb_streams)
	return AVERROR_INVALIDDATA;

	endframe = pop(br, pb);
	if (endframe < 0)
	return endframe;
	if (endframe) {
	bits = pop_length(br, pb);
	if (bits < 0)
	return bits;
	pop_int(br, pb, bits);
	pop(br, pb);
	bits = pop_length(br, pb);
	if (bits < 0)
	return bits;
	pop_int(br, pb, bits * 2 + 26);
	}

	pkt_size = pop_int(br, pb, 13) + 1;
	if (pkt_size > m->size)
	return AVERROR_INVALIDDATA;
	packet = s->streams[stream_index]->priv_data;
	if (!packet) {
	avio_skip(pb, pkt_size);
	continue;
	}

	ret = av_append_packet(pb, packet, pkt_size);
	if (ret < 0)
	return ret;
	if (endframe && packet->size > 0) {
	av_packet_move_ref(pkt, packet);
	pkt->pos = m->pos;
	pkt->stream_index = stream_index;
	if (s->streams[stream_index]->codecpar->codec_type == AVMEDIA_TYPE_VIDEO) {
	pkt->duration = 1;
	if (pkt->data[0] & 0x80)
	pkt->flags \|= AV_PKT_FLAG_KEY;
	} else {
	pkt->flags \|= AV_PKT_FLAG_KEY;
	}
	return ret;
	}
	}

	m->in_block = 0;

	if (m->flags % 2 == 0) {
	if (m->size <= 0)
	return AVERROR_INVALIDDATA;
	avio_seek(pb, m->pos + m->size, SEEK_SET);
	}
	}

	return AVERROR_EOF;
	}

	static int moflex_read_seek(AVFormatContext *s, int stream_index,
	int64_t pts, int flags)
	{
	MOFLEXDemuxContext *m = s->priv_data;

	m->in_block = 0;

	return -1;
	}

	static int moflex_read_close(AVFormatContext *s)
	{
	for (int i = 0; i < s->nb_streams; i++) {
	AVPacket *packet = s->streams[i]->priv_data;

	av_packet_free(&packet);
	s->streams[i]->priv_data = 0;
	}

	return 0;
	}

	AVInputFormat ff_moflex_demuxer = {
	.name = "moflex",
	.long_name = NULL_IF_CONFIG_SMALL("MobiClip MOFLEX"),
	.priv_data_size = sizeof(MOFLEXDemuxContext),
	.read_probe = moflex_probe,
	.read_header = moflex_read_header,
	.read_packet = moflex_read_packet,
	.read_seek = moflex_read_seek,
	.read_close = moflex_read_close,
	.extensions = "moflex",
	.flags = AVFMT_GENERIC_INDEX,
	};