[deb_ffmpeg.git] / ffmpeg / libavformat / mxg.c

/*
 * MxPEG clip file demuxer
 * Copyright (c) 2010 Anatoly Nenashev
 *
 * 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 "libavutil/channel_layout.h"
#include "libavutil/internal.h"
#include "libavutil/intreadwrite.h"
#include "libavcodec/mjpeg.h"
#include "avformat.h"
#include "internal.h"
#include "avio.h"

#define DEFAULT_PACKET_SIZE 1024
#define OVERREAD_SIZE 3

typedef struct MXGContext {
    uint8_t *buffer;
    uint8_t *buffer_ptr;
    uint8_t *soi_ptr;
    unsigned int buffer_size;
    int64_t dts;
    unsigned int cache_size;
} MXGContext;

static int mxg_read_header(AVFormatContext *s)
{
    AVStream *video_st, *audio_st;
    MXGContext *mxg = s->priv_data;

    /* video parameters will be extracted from the compressed bitstream */
    video_st = avformat_new_stream(s, NULL);
    if (!video_st)
        return AVERROR(ENOMEM);
    video_st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
    video_st->codec->codec_id = AV_CODEC_ID_MXPEG;
    avpriv_set_pts_info(video_st, 64, 1, 1000000);

    audio_st = avformat_new_stream(s, NULL);
    if (!audio_st)
        return AVERROR(ENOMEM);
    audio_st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
    audio_st->codec->codec_id = AV_CODEC_ID_PCM_ALAW;
    audio_st->codec->channels = 1;
    audio_st->codec->channel_layout = AV_CH_LAYOUT_MONO;
    audio_st->codec->sample_rate = 8000;
    audio_st->codec->bits_per_coded_sample = 8;
    audio_st->codec->block_align = 1;
    avpriv_set_pts_info(audio_st, 64, 1, 1000000);

    mxg->soi_ptr = mxg->buffer_ptr = mxg->buffer = 0;
    mxg->buffer_size = 0;
    mxg->dts = AV_NOPTS_VALUE;
    mxg->cache_size = 0;

    return 0;
}

static uint8_t* mxg_find_startmarker(uint8_t *p, uint8_t *end)
{
    for (; p < end - 3; p += 4) {
        uint32_t x = AV_RN32(p);

        if (x & (~(x+0x01010101)) & 0x80808080) {
            if (p[0] == 0xff) {
                return p;
            } else if (p[1] == 0xff) {
                return p+1;
            } else if (p[2] == 0xff) {
                return p+2;
            } else if (p[3] == 0xff) {
                return p+3;
            }
        }
    }

    for (; p < end; ++p) {
        if (*p == 0xff) return p;
    }

    return end;
}

static int mxg_update_cache(AVFormatContext *s, unsigned int cache_size)
{
    MXGContext *mxg = s->priv_data;
    unsigned int current_pos = mxg->buffer_ptr - mxg->buffer;
    unsigned int soi_pos;
    uint8_t *buffer;
    int ret;

    /* reallocate internal buffer */
    if (current_pos > current_pos + cache_size)
        return AVERROR(ENOMEM);
    soi_pos = mxg->soi_ptr - mxg->buffer;
    buffer = av_fast_realloc(mxg->buffer, &mxg->buffer_size,
                             current_pos + cache_size +
                             FF_INPUT_BUFFER_PADDING_SIZE);
    if (!buffer)
        return AVERROR(ENOMEM);
    mxg->buffer = buffer;
    mxg->buffer_ptr = mxg->buffer + current_pos;
    if (mxg->soi_ptr) mxg->soi_ptr = mxg->buffer + soi_pos;

    /* get data */
    ret = avio_read(s->pb, mxg->buffer_ptr + mxg->cache_size,
                     cache_size - mxg->cache_size);
    if (ret < 0)
        return ret;

    mxg->cache_size += ret;

    return ret;
}

static int mxg_read_packet(AVFormatContext *s, AVPacket *pkt)
{
    int ret;
    unsigned int size;
    uint8_t *startmarker_ptr, *end, *search_end, marker;
    MXGContext *mxg = s->priv_data;

    while (!avio_feof(s->pb) && !s->pb->error){
        if (mxg->cache_size <= OVERREAD_SIZE) {
            /* update internal buffer */
            ret = mxg_update_cache(s, DEFAULT_PACKET_SIZE + OVERREAD_SIZE);
            if (ret < 0)
                return ret;
        }
        end = mxg->buffer_ptr + mxg->cache_size;

        /* find start marker - 0xff */
        if (mxg->cache_size > OVERREAD_SIZE) {
            search_end = end - OVERREAD_SIZE;
            startmarker_ptr = mxg_find_startmarker(mxg->buffer_ptr, search_end);
        } else {
            search_end = end;
            startmarker_ptr = mxg_find_startmarker(mxg->buffer_ptr, search_end);
            if (startmarker_ptr >= search_end - 1 ||
                *(startmarker_ptr + 1) != EOI) break;
        }

        if (startmarker_ptr != search_end) { /* start marker found */
            marker = *(startmarker_ptr + 1);
            mxg->buffer_ptr = startmarker_ptr + 2;
            mxg->cache_size = end - mxg->buffer_ptr;

            if (marker == SOI) {
                mxg->soi_ptr = startmarker_ptr;
            } else if (marker == EOI) {
                if (!mxg->soi_ptr) {
                    av_log(s, AV_LOG_WARNING, "Found EOI before SOI, skipping\n");
                    continue;
                }

                pkt->pts = pkt->dts = mxg->dts;
                pkt->stream_index = 0;
#if FF_API_DESTRUCT_PACKET
FF_DISABLE_DEPRECATION_WARNINGS
                pkt->destruct = NULL;
FF_ENABLE_DEPRECATION_WARNINGS
#endif
                pkt->buf  = NULL;
                pkt->size = mxg->buffer_ptr - mxg->soi_ptr;
                pkt->data = mxg->soi_ptr;

                if (mxg->soi_ptr - mxg->buffer > mxg->cache_size) {
                    if (mxg->cache_size > 0) {
                        memcpy(mxg->buffer, mxg->buffer_ptr, mxg->cache_size);
                    }

                    mxg->buffer_ptr = mxg->buffer;
                }
                mxg->soi_ptr = 0;

                return pkt->size;
            } else if ( (SOF0 <= marker && marker <= SOF15) ||
                        (SOS  <= marker && marker <= COM) ) {
                /* all other markers that start marker segment also contain
                   length value (see specification for JPEG Annex B.1) */
                size = AV_RB16(mxg->buffer_ptr);
                if (size < 2)
                    return AVERROR(EINVAL);

                if (mxg->cache_size < size) {
                    ret = mxg_update_cache(s, size);
                    if (ret < 0)
                        return ret;
                    startmarker_ptr = mxg->buffer_ptr - 2;
                    mxg->cache_size = 0;
                } else {
                    mxg->cache_size -= size;
                }

                mxg->buffer_ptr += size;

                if (marker == APP13 && size >= 16) { /* audio data */
                    /* time (GMT) of first sample in usec since 1970, little-endian */
                    pkt->pts = pkt->dts = AV_RL64(startmarker_ptr + 8);
                    pkt->stream_index = 1;
#if FF_API_DESTRUCT_PACKET
FF_DISABLE_DEPRECATION_WARNINGS
                    pkt->destruct = NULL;
FF_ENABLE_DEPRECATION_WARNINGS
#endif
                    pkt->buf  = NULL;
                    pkt->size = size - 14;
                    pkt->data = startmarker_ptr + 16;

                    if (startmarker_ptr - mxg->buffer > mxg->cache_size) {
                        if (mxg->cache_size > 0) {
                            memcpy(mxg->buffer, mxg->buffer_ptr, mxg->cache_size);
                        }
                        mxg->buffer_ptr = mxg->buffer;
                    }

                    return pkt->size;
                } else if (marker == COM && size >= 18 &&
                           !strncmp(startmarker_ptr + 4, "MXF", 3)) {
                    /* time (GMT) of video frame in usec since 1970, little-endian */
                    mxg->dts = AV_RL64(startmarker_ptr + 12);
                }
            }
        } else {
            /* start marker not found */
            mxg->buffer_ptr = search_end;
            mxg->cache_size = OVERREAD_SIZE;
        }
    }

    return AVERROR_EOF;
}

static int mxg_close(struct AVFormatContext *s)
{
    MXGContext *mxg = s->priv_data;
    av_freep(&mxg->buffer);
    return 0;
}

AVInputFormat ff_mxg_demuxer = {
    .name           = "mxg",
    .long_name      = NULL_IF_CONFIG_SMALL("MxPEG clip"),
    .priv_data_size = sizeof(MXGContext),
    .read_header    = mxg_read_header,
    .read_packet    = mxg_read_packet,
    .read_close     = mxg_close,
    .extensions     = "mxg",
};
Commit	Line	Data
2ba45a60 DM	1	/*
	2	* MxPEG clip file demuxer
	3	* Copyright (c) 2010 Anatoly Nenashev
	4	*
	5	* This file is part of FFmpeg.
	6	*
	7	* FFmpeg is free software; you can redistribute it and/or
	8	* modify it under the terms of the GNU Lesser General Public
	9	* License as published by the Free Software Foundation; either
	10	* version 2.1 of the License, or (at your option) any later version.
	11	*
	12	* FFmpeg is distributed in the hope that it will be useful,
	13	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	14	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	15	* Lesser General Public License for more details.
	16	*
	17	* You should have received a copy of the GNU Lesser General Public
	18	* License along with FFmpeg; if not, write to the Free Software
	19	* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
	20	*/
	21
	22	#include "libavutil/channel_layout.h"
	23	#include "libavutil/internal.h"
	24	#include "libavutil/intreadwrite.h"
	25	#include "libavcodec/mjpeg.h"
	26	#include "avformat.h"
	27	#include "internal.h"
	28	#include "avio.h"
	29
	30	#define DEFAULT_PACKET_SIZE 1024
	31	#define OVERREAD_SIZE 3
	32
	33	typedef struct MXGContext {
	34	uint8_t *buffer;
	35	uint8_t *buffer_ptr;
	36	uint8_t *soi_ptr;
	37	unsigned int buffer_size;
	38	int64_t dts;
	39	unsigned int cache_size;
	40	} MXGContext;
	41
	42	static int mxg_read_header(AVFormatContext *s)
	43	{
	44	AVStream video_st, audio_st;
	45	MXGContext *mxg = s->priv_data;
	46
	47	/* video parameters will be extracted from the compressed bitstream */
	48	video_st = avformat_new_stream(s, NULL);
	49	if (!video_st)
	50	return AVERROR(ENOMEM);
	51	video_st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
	52	video_st->codec->codec_id = AV_CODEC_ID_MXPEG;
	53	avpriv_set_pts_info(video_st, 64, 1, 1000000);
	54
	55	audio_st = avformat_new_stream(s, NULL);
	56	if (!audio_st)
	57	return AVERROR(ENOMEM);
	58	audio_st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
	59	audio_st->codec->codec_id = AV_CODEC_ID_PCM_ALAW;
	60	audio_st->codec->channels = 1;
	61	audio_st->codec->channel_layout = AV_CH_LAYOUT_MONO;
	62	audio_st->codec->sample_rate = 8000;
	63	audio_st->codec->bits_per_coded_sample = 8;
	64	audio_st->codec->block_align = 1;
65	avpriv_set_pts_info(audio_st, 64, 1, 1000000);
66
67	mxg->soi_ptr = mxg->buffer_ptr = mxg->buffer = 0;
68	mxg->buffer_size = 0;
69	mxg->dts = AV_NOPTS_VALUE;
70	mxg->cache_size = 0;
71
72	return 0;
73	}
74
75	static uint8_t* mxg_find_startmarker(uint8_t p, uint8_t end)
76	{
77	for (; p < end - 3; p += 4) {
78	uint32_t x = AV_RN32(p);
79
80	if (x & (~(x+0x01010101)) & 0x80808080) {
81	if (p[0] == 0xff) {
82	return p;
83	} else if (p[1] == 0xff) {
84	return p+1;
85	} else if (p[2] == 0xff) {
86	return p+2;
87	} else if (p[3] == 0xff) {
88	return p+3;
89	}
90	}
91	}
92
93	for (; p < end; ++p) {
94	if (*p == 0xff) return p;
95	}
96
97	return end;
98	}
99
100	static int mxg_update_cache(AVFormatContext *s, unsigned int cache_size)
101	{
102	MXGContext *mxg = s->priv_data;
103	unsigned int current_pos = mxg->buffer_ptr - mxg->buffer;
104	unsigned int soi_pos;
105	uint8_t *buffer;
106	int ret;
107
108	/* reallocate internal buffer */
109	if (current_pos > current_pos + cache_size)
110	return AVERROR(ENOMEM);
111	soi_pos = mxg->soi_ptr - mxg->buffer;
112	buffer = av_fast_realloc(mxg->buffer, &mxg->buffer_size,
113	current_pos + cache_size +
114	FF_INPUT_BUFFER_PADDING_SIZE);
115	if (!buffer)
116	return AVERROR(ENOMEM);
117	mxg->buffer = buffer;
118	mxg->buffer_ptr = mxg->buffer + current_pos;
119	if (mxg->soi_ptr) mxg->soi_ptr = mxg->buffer + soi_pos;
120
121	/* get data */
122	ret = avio_read(s->pb, mxg->buffer_ptr + mxg->cache_size,
123	cache_size - mxg->cache_size);
124	if (ret < 0)
125	return ret;
126
127	mxg->cache_size += ret;
128
129	return ret;
130	}
131
132	static int mxg_read_packet(AVFormatContext s, AVPacket pkt)
133	{
134	int ret;
135	unsigned int size;
136	uint8_t startmarker_ptr, end, *search_end, marker;
137	MXGContext *mxg = s->priv_data;
138
139	while (!avio_feof(s->pb) && !s->pb->error){
140	if (mxg->cache_size <= OVERREAD_SIZE) {
141	/* update internal buffer */
142	ret = mxg_update_cache(s, DEFAULT_PACKET_SIZE + OVERREAD_SIZE);
143	if (ret < 0)
144	return ret;
145	}
146	end = mxg->buffer_ptr + mxg->cache_size;
147
148	/* find start marker - 0xff */
149	if (mxg->cache_size > OVERREAD_SIZE) {
150	search_end = end - OVERREAD_SIZE;
151	startmarker_ptr = mxg_find_startmarker(mxg->buffer_ptr, search_end);
152	} else {
153	search_end = end;
154	startmarker_ptr = mxg_find_startmarker(mxg->buffer_ptr, search_end);
155	if (startmarker_ptr >= search_end - 1 \|\|
156	*(startmarker_ptr + 1) != EOI) break;
157	}
158
159	if (startmarker_ptr != search_end) { /* start marker found */
160	marker = *(startmarker_ptr + 1);
161	mxg->buffer_ptr = startmarker_ptr + 2;
162	mxg->cache_size = end - mxg->buffer_ptr;
163
164	if (marker == SOI) {
165	mxg->soi_ptr = startmarker_ptr;
166	} else if (marker == EOI) {
167	if (!mxg->soi_ptr) {
168	av_log(s, AV_LOG_WARNING, "Found EOI before SOI, skipping\n");
169	continue;
170	}
171
172	pkt->pts = pkt->dts = mxg->dts;
173	pkt->stream_index = 0;
174	#if FF_API_DESTRUCT_PACKET
175	FF_DISABLE_DEPRECATION_WARNINGS
176	pkt->destruct = NULL;
177	FF_ENABLE_DEPRECATION_WARNINGS
178	#endif
179	pkt->buf = NULL;
180	pkt->size = mxg->buffer_ptr - mxg->soi_ptr;
181	pkt->data = mxg->soi_ptr;
182
183	if (mxg->soi_ptr - mxg->buffer > mxg->cache_size) {
184	if (mxg->cache_size > 0) {
185	memcpy(mxg->buffer, mxg->buffer_ptr, mxg->cache_size);
186	}
187
188	mxg->buffer_ptr = mxg->buffer;
189	}
190	mxg->soi_ptr = 0;
191
192	return pkt->size;
193	} else if ( (SOF0 <= marker && marker <= SOF15) \|\|
194	(SOS <= marker && marker <= COM) ) {
195	/* all other markers that start marker segment also contain
196	length value (see specification for JPEG Annex B.1) */
197	size = AV_RB16(mxg->buffer_ptr);
198	if (size < 2)
199	return AVERROR(EINVAL);
200
201	if (mxg->cache_size < size) {
202	ret = mxg_update_cache(s, size);
203	if (ret < 0)
204	return ret;
205	startmarker_ptr = mxg->buffer_ptr - 2;
206	mxg->cache_size = 0;
207	} else {
208	mxg->cache_size -= size;
209	}
210
211	mxg->buffer_ptr += size;
212
213	if (marker == APP13 && size >= 16) { /* audio data */
214	/* time (GMT) of first sample in usec since 1970, little-endian */
215	pkt->pts = pkt->dts = AV_RL64(startmarker_ptr + 8);
216	pkt->stream_index = 1;
217	#if FF_API_DESTRUCT_PACKET
218	FF_DISABLE_DEPRECATION_WARNINGS
219	pkt->destruct = NULL;
220	FF_ENABLE_DEPRECATION_WARNINGS
221	#endif
222	pkt->buf = NULL;
223	pkt->size = size - 14;
224	pkt->data = startmarker_ptr + 16;
225
226	if (startmarker_ptr - mxg->buffer > mxg->cache_size) {
227	if (mxg->cache_size > 0) {
228	memcpy(mxg->buffer, mxg->buffer_ptr, mxg->cache_size);
229	}
230	mxg->buffer_ptr = mxg->buffer;
231	}
232
233	return pkt->size;
234	} else if (marker == COM && size >= 18 &&
235	!strncmp(startmarker_ptr + 4, "MXF", 3)) {
236	/* time (GMT) of video frame in usec since 1970, little-endian */
237	mxg->dts = AV_RL64(startmarker_ptr + 12);
238	}
239	}
240	} else {
241	/* start marker not found */
242	mxg->buffer_ptr = search_end;
243	mxg->cache_size = OVERREAD_SIZE;
244	}
245	}
246
247	return AVERROR_EOF;
248	}
249
250	static int mxg_close(struct AVFormatContext *s)
251	{
252	MXGContext *mxg = s->priv_data;
253	av_freep(&mxg->buffer);
254	return 0;
255	}
256
257	AVInputFormat ff_mxg_demuxer = {
258	.name = "mxg",
259	.long_name = NULL_IF_CONFIG_SMALL("MxPEG clip"),
260	.priv_data_size = sizeof(MXGContext),
261	.read_header = mxg_read_header,
262	.read_packet = mxg_read_packet,
263	.read_close = mxg_close,
264	.extensions = "mxg",
265	};