1/*
2 * LXF demuxer
3 * Copyright (c) 2010 Tomas H��rdin
4 *
5 * This file is part of Libav.
6 *
7 * Libav 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 * Libav 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 Libav; 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/intreadwrite.h"
23#include "avformat.h"
24#include "internal.h"
25#include "riff.h"
26
27#define LXF_PACKET_HEADER_SIZE  60
28#define LXF_HEADER_DATA_SIZE    120
29#define LXF_IDENT               "LEITCH\0"
30#define LXF_IDENT_LENGTH        8
31#define LXF_SAMPLERATE          48000
32#define LXF_MAX_AUDIO_PACKET    (8008*15*4) ///< 15-channel 32-bit NTSC audio frame
33
34static const AVCodecTag lxf_tags[] = {
35    { CODEC_ID_MJPEG,       0 },
36    { CODEC_ID_MPEG1VIDEO,  1 },
37    { CODEC_ID_MPEG2VIDEO,  2 },    //MpMl, 4:2:0
38    { CODEC_ID_MPEG2VIDEO,  3 },    //MpPl, 4:2:2
39    { CODEC_ID_DVVIDEO,     4 },    //DV25
40    { CODEC_ID_DVVIDEO,     5 },    //DVCPRO
41    { CODEC_ID_DVVIDEO,     6 },    //DVCPRO50
42    { CODEC_ID_RAWVIDEO,    7 },    //PIX_FMT_ARGB, where alpha is used for chroma keying
43    { CODEC_ID_RAWVIDEO,    8 },    //16-bit chroma key
44    { CODEC_ID_MPEG2VIDEO,  9 },    //4:2:2 CBP ("Constrained Bytes per Gop")
45    { CODEC_ID_NONE,        0 },
46};
47
48typedef struct {
49    int channels;                       ///< number of audio channels. zero means no audio
50    uint8_t temp[LXF_MAX_AUDIO_PACKET]; ///< temp buffer for de-planarizing the audio data
51    int frame_number;                   ///< current video frame
52} LXFDemuxContext;
53
54static int lxf_probe(AVProbeData *p)
55{
56    if (!memcmp(p->buf, LXF_IDENT, LXF_IDENT_LENGTH))
57        return AVPROBE_SCORE_MAX;
58
59    return 0;
60}
61
62/**
63 * Verify the checksum of an LXF packet header
64 *
65 * @param[in] header the packet header to check
66 * @return zero if the checksum is OK, non-zero otherwise
67 */
68static int check_checksum(const uint8_t *header)
69{
70    int x;
71    uint32_t sum = 0;
72
73    for (x = 0; x < LXF_PACKET_HEADER_SIZE; x += 4)
74        sum += AV_RL32(&header[x]);
75
76    return sum;
77}
78
79/**
80 * Read input until we find the next ident. If found, copy it to the header buffer
81 *
82 * @param[out] header where to copy the ident to
83 * @return 0 if an ident was found, < 0 on I/O error
84 */
85static int sync(AVFormatContext *s, uint8_t *header)
86{
87    uint8_t buf[LXF_IDENT_LENGTH];
88    int ret;
89
90    if ((ret = avio_read(s->pb, buf, LXF_IDENT_LENGTH)) != LXF_IDENT_LENGTH)
91        return ret < 0 ? ret : AVERROR_EOF;
92
93    while (memcmp(buf, LXF_IDENT, LXF_IDENT_LENGTH)) {
94        if (s->pb->eof_reached)
95            return AVERROR_EOF;
96
97        memmove(buf, &buf[1], LXF_IDENT_LENGTH-1);
98        buf[LXF_IDENT_LENGTH-1] = avio_r8(s->pb);
99    }
100
101    memcpy(header, LXF_IDENT, LXF_IDENT_LENGTH);
102
103    return 0;
104}
105
106/**
107 * Read and checksum the next packet header
108 *
109 * @param[out] header the read packet header
110 * @param[out] format context dependent format information
111 * @return the size of the payload following the header or < 0 on failure
112 */
113static int get_packet_header(AVFormatContext *s, uint8_t *header, uint32_t *format)
114{
115    AVIOContext   *pb  = s->pb;
116    int track_size, samples, ret;
117    AVStream *st;
118
119    //find and read the ident
120    if ((ret = sync(s, header)) < 0)
121        return ret;
122
123    //read the rest of the packet header
124    if ((ret = avio_read(pb, header + LXF_IDENT_LENGTH,
125                          LXF_PACKET_HEADER_SIZE - LXF_IDENT_LENGTH)) !=
126                          LXF_PACKET_HEADER_SIZE - LXF_IDENT_LENGTH) {
127        return ret < 0 ? ret : AVERROR_EOF;
128    }
129
130    if (check_checksum(header))
131        av_log(s, AV_LOG_ERROR, "checksum error\n");
132
133    *format = AV_RL32(&header[32]);
134    ret     = AV_RL32(&header[36]);
135
136    //type
137    switch (AV_RL32(&header[16])) {
138    case 0:
139        //video
140        //skip VBI data and metadata
141        avio_skip(pb, (int64_t)(uint32_t)AV_RL32(&header[44]) +
142                      (int64_t)(uint32_t)AV_RL32(&header[52]));
143        break;
144    case 1:
145        //audio
146        if (!(st = s->streams[1])) {
147            av_log(s, AV_LOG_INFO, "got audio packet, but no audio stream present\n");
148            break;
149        }
150
151        //set codec based on specified audio bitdepth
152        //we only support tightly packed 16-, 20-, 24- and 32-bit PCM at the moment
153        *format                          = AV_RL32(&header[40]);
154        st->codec->bits_per_coded_sample = (*format >> 6) & 0x3F;
155
156        if (st->codec->bits_per_coded_sample != (*format & 0x3F)) {
157            av_log(s, AV_LOG_WARNING, "only tightly packed PCM currently supported\n");
158            return AVERROR_PATCHWELCOME;
159        }
160
161        switch (st->codec->bits_per_coded_sample) {
162        case 16: st->codec->codec_id = CODEC_ID_PCM_S16LE; break;
163        case 20: st->codec->codec_id = CODEC_ID_PCM_LXF;   break;
164        case 24: st->codec->codec_id = CODEC_ID_PCM_S24LE; break;
165        case 32: st->codec->codec_id = CODEC_ID_PCM_S32LE; break;
166        default:
167            av_log(s, AV_LOG_WARNING,
168                   "only 16-, 20-, 24- and 32-bit PCM currently supported\n");
169            return AVERROR_PATCHWELCOME;
170        }
171
172        track_size = AV_RL32(&header[48]);
173        samples = track_size * 8 / st->codec->bits_per_coded_sample;
174
175        //use audio packet size to determine video standard
176        //for NTSC we have one 8008-sample audio frame per five video frames
177        if (samples == LXF_SAMPLERATE * 5005 / 30000) {
178            avpriv_set_pts_info(s->streams[0], 64, 1001, 30000);
179        } else {
180            //assume PAL, but warn if we don't have 1920 samples
181            if (samples != LXF_SAMPLERATE / 25)
182                av_log(s, AV_LOG_WARNING,
183                       "video doesn't seem to be PAL or NTSC. guessing PAL\n");
184
185            avpriv_set_pts_info(s->streams[0], 64, 1, 25);
186        }
187
188        //TODO: warning if track mask != (1 << channels) - 1?
189        ret = av_popcount(AV_RL32(&header[44])) * track_size;
190
191        break;
192    default:
193        break;
194    }
195
196    return ret;
197}
198
199static int lxf_read_header(AVFormatContext *s, AVFormatParameters *ap)
200{
201    LXFDemuxContext *lxf = s->priv_data;
202    AVIOContext   *pb  = s->pb;
203    uint8_t header[LXF_PACKET_HEADER_SIZE], header_data[LXF_HEADER_DATA_SIZE];
204    int ret;
205    AVStream *st;
206    uint32_t format, video_params, disk_params;
207    uint16_t record_date, expiration_date;
208
209    if ((ret = get_packet_header(s, header, &format)) < 0)
210        return ret;
211
212    if (ret != LXF_HEADER_DATA_SIZE) {
213        av_log(s, AV_LOG_ERROR, "expected %d B size header, got %d\n",
214               LXF_HEADER_DATA_SIZE, ret);
215        return AVERROR_INVALIDDATA;
216    }
217
218    if ((ret = avio_read(pb, header_data, LXF_HEADER_DATA_SIZE)) != LXF_HEADER_DATA_SIZE)
219        return ret < 0 ? ret : AVERROR_EOF;
220
221    if (!(st = avformat_new_stream(s, NULL)))
222        return AVERROR(ENOMEM);
223
224    st->duration          = AV_RL32(&header_data[32]);
225    video_params          = AV_RL32(&header_data[40]);
226    record_date           = AV_RL16(&header_data[56]);
227    expiration_date       = AV_RL16(&header_data[58]);
228    disk_params           = AV_RL32(&header_data[116]);
229
230    st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
231    st->codec->bit_rate   = 1000000 * ((video_params >> 14) & 0xFF);
232    st->codec->codec_tag  = video_params & 0xF;
233    st->codec->codec_id   = ff_codec_get_id(lxf_tags, st->codec->codec_tag);
234
235    av_log(s, AV_LOG_DEBUG, "record: %x = %i-%02i-%02i\n",
236           record_date, 1900 + (record_date & 0x7F), (record_date >> 7) & 0xF,
237           (record_date >> 11) & 0x1F);
238
239    av_log(s, AV_LOG_DEBUG, "expire: %x = %i-%02i-%02i\n",
240           expiration_date, 1900 + (expiration_date & 0x7F), (expiration_date >> 7) & 0xF,
241           (expiration_date >> 11) & 0x1F);
242
243    if ((video_params >> 22) & 1)
244        av_log(s, AV_LOG_WARNING, "VBI data not yet supported\n");
245
246    if ((lxf->channels = (disk_params >> 2) & 0xF)) {
247        if (!(st = avformat_new_stream(s, NULL)))
248            return AVERROR(ENOMEM);
249
250        st->codec->codec_type  = AVMEDIA_TYPE_AUDIO;
251        st->codec->sample_rate = LXF_SAMPLERATE;
252        st->codec->channels    = lxf->channels;
253
254        avpriv_set_pts_info(st, 64, 1, st->codec->sample_rate);
255    }
256
257    if (format == 1) {
258        //skip extended field data
259        avio_skip(s->pb, (uint32_t)AV_RL32(&header[40]));
260    }
261
262    return 0;
263}
264
265/**
266 * De-planerize the PCM data in lxf->temp
267 * FIXME: remove this once support for planar audio is added to libavcodec
268 *
269 * @param[out] out where to write the de-planerized data to
270 * @param[in] bytes the total size of the PCM data
271 */
272static void deplanarize(LXFDemuxContext *lxf, AVStream *ast, uint8_t *out, int bytes)
273{
274    int x, y, z, i, bytes_per_sample = ast->codec->bits_per_coded_sample >> 3;
275
276    for (z = i = 0; z < lxf->channels; z++)
277        for (y = 0; y < bytes / bytes_per_sample / lxf->channels; y++)
278            for (x = 0; x < bytes_per_sample; x++, i++)
279                out[x + bytes_per_sample*(z + y*lxf->channels)] = lxf->temp[i];
280}
281
282static int lxf_read_packet(AVFormatContext *s, AVPacket *pkt)
283{
284    LXFDemuxContext *lxf = s->priv_data;
285    AVIOContext   *pb  = s->pb;
286    uint8_t header[LXF_PACKET_HEADER_SIZE], *buf;
287    AVStream *ast = NULL;
288    uint32_t stream, format;
289    int ret, ret2;
290
291    if ((ret = get_packet_header(s, header, &format)) < 0)
292        return ret;
293
294    stream = AV_RL32(&header[16]);
295
296    if (stream > 1) {
297        av_log(s, AV_LOG_WARNING, "got packet with illegal stream index %u\n", stream);
298        return AVERROR(EAGAIN);
299    }
300
301    if (stream == 1 && !(ast = s->streams[1])) {
302        av_log(s, AV_LOG_ERROR, "got audio packet without having an audio stream\n");
303        return AVERROR_INVALIDDATA;
304    }
305
306    //make sure the data fits in the de-planerization buffer
307    if (ast && ret > LXF_MAX_AUDIO_PACKET) {
308        av_log(s, AV_LOG_ERROR, "audio packet too large (%i > %i)\n",
309            ret, LXF_MAX_AUDIO_PACKET);
310        return AVERROR_INVALIDDATA;
311    }
312
313    if ((ret2 = av_new_packet(pkt, ret)) < 0)
314        return ret2;
315
316    //read non-20-bit audio data into lxf->temp so we can deplanarize it
317    buf = ast && ast->codec->codec_id != CODEC_ID_PCM_LXF ? lxf->temp : pkt->data;
318
319    if ((ret2 = avio_read(pb, buf, ret)) != ret) {
320        av_free_packet(pkt);
321        return ret2 < 0 ? ret2 : AVERROR_EOF;
322    }
323
324    pkt->stream_index = stream;
325
326    if (ast) {
327        if(ast->codec->codec_id != CODEC_ID_PCM_LXF)
328            deplanarize(lxf, ast, pkt->data, ret);
329    } else {
330        //picture type (0 = closed I, 1 = open I, 2 = P, 3 = B)
331        if (((format >> 22) & 0x3) < 2)
332            pkt->flags |= AV_PKT_FLAG_KEY;
333
334        pkt->dts = lxf->frame_number++;
335    }
336
337    return ret;
338}
339
340AVInputFormat ff_lxf_demuxer = {
341    .name           = "lxf",
342    .long_name      = NULL_IF_CONFIG_SMALL("VR native stream format (LXF)"),
343    .priv_data_size = sizeof(LXFDemuxContext),
344    .read_probe     = lxf_probe,
345    .read_header    = lxf_read_header,
346    .read_packet    = lxf_read_packet,
347    .codec_tag      = (const AVCodecTag* const []){lxf_tags, 0},
348};
349
350