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FFmpeg/libavformat/ffmdec.c

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  1. /*

  2.  * FFM (ffserver live feed) demuxer

  3.  * Copyright (c) 2001 Fabrice Bellard

  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 <stdint.h>

  23. 

  24. #include "libavutil/imgutils.h"

  25. #include "libavutil/internal.h"

  26. #include "libavutil/intreadwrite.h"

  27. #include "libavutil/intfloat.h"

  28. #include "libavutil/opt.h"

  29. #include "libavutil/avassert.h"

  30. #include "libavutil/avstring.h"

  31. #include "libavutil/pixdesc.h"

  32. #include "libavcodec/internal.h"

  33. #include "avformat.h"

  34. #include "internal.h"

  35. #include "ffm.h"

  36. #include "avio_internal.h"

  37. 

  38. static int ffm_is_avail_data(AVFormatContext *s, int size)

  39. {

  40.     FFMContext *ffm = s->priv_data;

  41.     int64_t pos, avail_size;

  42.     ptrdiff_t len;

  43. 

  44.     len = ffm->packet_end - ffm->packet_ptr;

  45.     if (size <= len)

  46.         return 1;

  47.     pos = avio_tell(s->pb);

  48.     if (!ffm->write_index) {

  49.         if (pos == ffm->file_size)

  50.             return AVERROR_EOF;

  51.         avail_size = ffm->file_size - pos;

  52.     } else {

  53.     if (pos == ffm->write_index) {

  54.         /* exactly at the end of stream */

  55.         if (ffm->server_attached)

  56.             return AVERROR(EAGAIN);

  57.         else

  58.             return AVERROR_INVALIDDATA;

  59.     } else if (pos < ffm->write_index) {

  60.         avail_size = ffm->write_index - pos;

  61.     } else {

  62.         avail_size = (ffm->file_size - pos) + (ffm->write_index - FFM_PACKET_SIZE);

  63.     }

  64.     }

  65.     avail_size = (avail_size / ffm->packet_size) * (ffm->packet_size - FFM_HEADER_SIZE) + len;

  66.     if (size <= avail_size)

  67.         return 1;

  68.     else if (ffm->server_attached)

  69.         return AVERROR(EAGAIN);

  70.     else

  71.         return AVERROR_INVALIDDATA;

  72. }

  73. 

  74. static int ffm_resync(AVFormatContext *s, uint32_t state)

  75. {

  76.     av_log(s, AV_LOG_ERROR, "resyncing\n");

  77.     while (state != PACKET_ID) {

  78.         if (avio_feof(s->pb)) {

  79.             av_log(s, AV_LOG_ERROR, "cannot find FFM syncword\n");

  80.             return -1;

  81.         }

  82.         state = (state << 8) | avio_r8(s->pb);

  83.     }

  84.     return 0;

  85. }

  86. 

  87. /* first is true if we read the frame header */

  88. static int ffm_read_data(AVFormatContext *s,

  89.                          uint8_t *buf, int size, int header)

  90. {

  91.     FFMContext *ffm = s->priv_data;

  92.     AVIOContext *pb = s->pb;

  93.     int fill_size, size1, frame_offset;

  94.     uint32_t id;

  95.     ptrdiff_t len;

  96.     int64_t last_pos = -1;

  97. 

  98.     size1 = size;

  99.     while (size > 0) {

  100.     redo:

  101.         len = ffm->packet_end - ffm->packet_ptr;

  102.         if (len < 0)

  103.             return -1;

  104.         if (len > size)

  105.             len = size;

  106.         if (len == 0) {

  107.             if (avio_tell(pb) == ffm->file_size) {

  108.                 if (ffm->server_attached) {

  109.                     avio_seek(pb, ffm->packet_size, SEEK_SET);

  110.                 } else

  111.                     return AVERROR_EOF;

  112.             }

  113.     retry_read:

  114.             if (pb->buffer_size != ffm->packet_size) {

  115.                 int64_t tell = avio_tell(pb);

  116.                 int ret = ffio_set_buf_size(pb, ffm->packet_size);

  117.                 if (ret < 0)

  118.                     return ret;

  119.                 avio_seek(pb, tell, SEEK_SET);

  120.             }

  121.             id = avio_rb16(pb); /* PACKET_ID */

  122.             if (id != PACKET_ID) {

  123.                 if (ffm_resync(s, id) < 0)

  124.                     return -1;

  125.                 last_pos = avio_tell(pb);

  126.             }

  127.             fill_size = avio_rb16(pb);

  128.             ffm->dts = avio_rb64(pb);

  129.             frame_offset = avio_rb16(pb);

  130.             avio_read(pb, ffm->packet, ffm->packet_size - FFM_HEADER_SIZE);

  131.             if (ffm->packet_size < FFM_HEADER_SIZE + fill_size || frame_offset < 0) {

  132.                 return -1;

  133.             }

  134.             ffm->packet_end = ffm->packet + (ffm->packet_size - FFM_HEADER_SIZE - fill_size);

  135.             /* if first packet or resynchronization packet, we must

  136.                handle it specifically */

  137.             if (ffm->first_packet || (frame_offset & 0x8000)) {

  138.                 if (!frame_offset) {

  139.                     /* This packet has no frame headers in it */

  140.                     if (avio_tell(pb) >= ffm->packet_size * 3LL) {

  141.                         int64_t seekback = FFMIN(ffm->packet_size * 2LL, avio_tell(pb) - last_pos);

  142.                         seekback = FFMAX(seekback, 0);

  143.                         avio_seek(pb, -seekback, SEEK_CUR);

  144.                         goto retry_read;

  145.                     }

  146.                     /* This is bad, we cannot find a valid frame header */

  147.                     return 0;

  148.                 }

  149.                 ffm->first_packet = 0;

  150.                 if ((frame_offset & 0x7fff) < FFM_HEADER_SIZE) {

  151.                     ffm->packet_end = ffm->packet_ptr;

  152.                     return -1;

  153.                 }

  154.                 ffm->packet_ptr = ffm->packet + (frame_offset & 0x7fff) - FFM_HEADER_SIZE;

  155.                 if (!header)

  156.                     break;

  157.             } else {

  158.                 ffm->packet_ptr = ffm->packet;

  159.             }

  160.             goto redo;

  161.         }

  162.         memcpy(buf, ffm->packet_ptr, len);

  163.         buf += len;

  164.         ffm->packet_ptr += len;

  165.         size -= len;

  166.         header = 0;

  167.     }

  168.     return size1 - size;

  169. }

  170. 

  171. /* ensure that actual seeking happens between FFM_PACKET_SIZE

  172.    and file_size - FFM_PACKET_SIZE */

  173. static int64_t ffm_seek1(AVFormatContext *s, int64_t pos1)

  174. {

  175.     FFMContext *ffm = s->priv_data;

  176.     AVIOContext *pb = s->pb;

  177.     int64_t pos;

  178. 

  179.     pos = FFMIN(pos1, ffm->file_size - FFM_PACKET_SIZE);

  180.     pos = FFMAX(pos, FFM_PACKET_SIZE);

  181.     ff_dlog(s, "seek to %"PRIx64" -> %"PRIx64"\n", pos1, pos);

  182.     return avio_seek(pb, pos, SEEK_SET);

  183. }

  184. 

  185. static int64_t get_dts(AVFormatContext *s, int64_t pos)

  186. {

  187.     AVIOContext *pb = s->pb;

  188.     int64_t dts;

  189. 

  190.     ffm_seek1(s, pos);

  191.     avio_skip(pb, 4);

  192.     dts = avio_rb64(pb);

  193.     ff_dlog(s, "dts=%0.6f\n", dts / 1000000.0);

  194.     return dts;

  195. }

  196. 

  197. static void adjust_write_index(AVFormatContext *s)

  198. {

  199.     FFMContext *ffm = s->priv_data;

  200.     AVIOContext *pb = s->pb;

  201.     int64_t pts;

  202.     //int64_t orig_write_index = ffm->write_index;

  203.     int64_t pos_min, pos_max;

  204.     int64_t pts_start;

  205.     int64_t ptr = avio_tell(pb);

  206. 

  207. 

  208.     pos_min = 0;

  209.     pos_max = ffm->file_size - 2 * FFM_PACKET_SIZE;

  210. 

  211.     pts_start = get_dts(s, pos_min);

  212. 

  213.     pts = get_dts(s, pos_max);

  214. 

  215.     if (pts - 100000 > pts_start)

  216.         goto end;

  217. 

  218.     ffm->write_index = FFM_PACKET_SIZE;

  219. 

  220.     pts_start = get_dts(s, pos_min);

  221. 

  222.     pts = get_dts(s, pos_max);

  223. 

  224.     if (pts - 100000 <= pts_start) {

  225.         while (1) {

  226.             int64_t newpos;

  227.             int64_t newpts;

  228. 

  229.             newpos = ((pos_max + pos_min) / (2 * FFM_PACKET_SIZE)) * FFM_PACKET_SIZE;

  230. 

  231.             if (newpos == pos_min)

  232.                 break;

  233. 

  234.             newpts = get_dts(s, newpos);

  235. 

  236.             if (newpts - 100000 <= pts) {

  237.                 pos_max = newpos;

  238.                 pts = newpts;

  239.             } else {

  240.                 pos_min = newpos;

  241.             }

  242.         }

  243.         ffm->write_index += pos_max;

  244.     }

  245. 

  246.  end:

  247.     avio_seek(pb, ptr, SEEK_SET);

  248. }

  249. 

  250. 

  251. static int ffm_append_recommended_configuration(AVStream *st, char **conf)

  252. {

  253.     int ret;

  254.     size_t newsize;

  255.     av_assert0(conf && st);

  256.     if (!*conf)

  257.         return 0;

  258.     if (!st->recommended_encoder_configuration) {

  259.         st->recommended_encoder_configuration = *conf;

  260.         *conf = 0;

  261.         return 0;

  262.     }

  263.     newsize = strlen(*conf) + strlen(st->recommended_encoder_configuration) + 2;

  264.     if ((ret = av_reallocp(&st->recommended_encoder_configuration, newsize)) < 0)

  265.         return ret;

  266.     av_strlcat(st->recommended_encoder_configuration, ",", newsize);

  267.     av_strlcat(st->recommended_encoder_configuration, *conf, newsize);

  268.     av_freep(conf);

  269.     return 0;

  270. }

  271. 

  272. #define VALIDATE_PARAMETER(parameter, name, check) {                              \

  273.     if (check) {                                                                  \

  274.         av_log(codec, AV_LOG_ERROR, "Invalid " name " %d\n", codecpar->parameter);   \

  275.         ret = AVERROR_INVALIDDATA;                                                \

  276.         goto fail;                                                                \

  277.     }                                                                             \

  278. }

  279. 

  280. static int ffm2_read_header(AVFormatContext *s)

  281. {

  282.     FFMContext *ffm = s->priv_data;

  283.     AVStream *st;

  284.     AVIOContext *pb = s->pb;

  285.     AVCodecContext *codec, *dummy_codec = NULL;

  286.     AVCodecParameters *codecpar;

  287.     const AVCodecDescriptor *codec_desc;

  288.     int ret;

  289.     int f_main = 0, f_cprv = -1, f_stvi = -1, f_stau = -1;

  290.     AVCodec *enc;

  291.     char *buffer;

  292. 

  293.     ffm->packet_size = avio_rb32(pb);

  294.     if (ffm->packet_size != FFM_PACKET_SIZE) {

  295.         av_log(s, AV_LOG_ERROR, "Invalid packet size %d, expected size was %d\n",

  296.                ffm->packet_size, FFM_PACKET_SIZE);

  297.         ret = AVERROR_INVALIDDATA;

  298.         goto fail;

  299.     }

  300. 

  301.     ffm->write_index = avio_rb64(pb);

  302.     /* get also filesize */

  303.     if (pb->seekable) {

  304.         ffm->file_size = avio_size(pb);

  305.         if (ffm->write_index && 0)

  306.             adjust_write_index(s);

  307.     } else {

  308.         ffm->file_size = (UINT64_C(1) << 63) - 1;

  309.     }

  310.     dummy_codec = avcodec_alloc_context3(NULL);

  311. 

  312.     while(!avio_feof(pb)) {

  313.         unsigned id = avio_rb32(pb);

  314.         unsigned size = avio_rb32(pb);

  315.         int64_t next = avio_tell(pb) + size;

  316.         char rc_eq_buf[128];

  317. 

  318.         if(!id)

  319.             break;

  320. 

  321.         switch(id) {

  322.         case MKBETAG('M', 'A', 'I', 'N'):

  323.             if (f_main++) {

  324.                 ret = AVERROR(EINVAL);

  325.                 goto fail;

  326.             }

  327.             avio_rb32(pb); /* nb_streams */

  328.             avio_rb32(pb); /* total bitrate */

  329.             break;

  330.         case MKBETAG('C', 'O', 'M', 'M'):

  331.             f_cprv = f_stvi = f_stau = 0;

  332.             st = avformat_new_stream(s, NULL);

  333.             if (!st) {

  334.                 ret = AVERROR(ENOMEM);

  335.                 goto fail;

  336.             }

  337. 

  338.             avpriv_set_pts_info(st, 64, 1, 1000000);

  339. 

  340.             codec = st->codec;

  341.             codecpar = st->codecpar;

  342.             /* generic info */

  343.             codecpar->codec_id = avio_rb32(pb);

  344.             codec_desc = avcodec_descriptor_get(codecpar->codec_id);

  345.             if (!codec_desc) {

  346.                 av_log(s, AV_LOG_ERROR, "Invalid codec id: %d\n", codecpar->codec_id);

  347.                 codecpar->codec_id = AV_CODEC_ID_NONE;

  348.                 ret = AVERROR_INVALIDDATA;

  349.                 goto fail;

  350.             }

  351.             codecpar->codec_type = avio_r8(pb);

  352.             if (codecpar->codec_type != codec_desc->type) {

  353.                 av_log(s, AV_LOG_ERROR, "Codec type mismatch: expected %d, found %d\n",

  354.                        codec_desc->type, codecpar->codec_type);

  355.                 codecpar->codec_id = AV_CODEC_ID_NONE;

  356.                 codecpar->codec_type = AVMEDIA_TYPE_UNKNOWN;

  357.                 ret = AVERROR_INVALIDDATA;

  358.                 goto fail;

  359.             }

  360.             codecpar->bit_rate = avio_rb32(pb);

  361.             if (codecpar->bit_rate < 0) {

  362.                 av_log(codec, AV_LOG_ERROR, "Invalid bit rate %"PRId64"\n", codecpar->bit_rate);

  363.                 ret = AVERROR_INVALIDDATA;

  364.                 goto fail;

  365.             }

  366.             codec->flags = avio_rb32(pb);

  367.             codec->flags2 = avio_rb32(pb);

  368.             codec->debug = avio_rb32(pb);

  369.             if (codec->flags & AV_CODEC_FLAG_GLOBAL_HEADER) {

  370.                 int size = avio_rb32(pb);

  371.                 if (size < 0 || size >= FF_MAX_EXTRADATA_SIZE) {

  372.                     av_log(s, AV_LOG_ERROR, "Invalid extradata size %d\n", size);

  373.                     ret = AVERROR_INVALIDDATA;

  374.                     goto fail;

  375.                 }

  376.                 codecpar->extradata = av_mallocz(size + AV_INPUT_BUFFER_PADDING_SIZE);

  377.                 if (!codecpar->extradata)

  378.                     return AVERROR(ENOMEM);

  379.                 codecpar->extradata_size = size;

  380.                 avio_read(pb, codecpar->extradata, size);

  381.             }

  382.             break;

  383.         case MKBETAG('S', 'T', 'V', 'I'):

  384.             if (f_stvi++ || codecpar->codec_type != AVMEDIA_TYPE_VIDEO) {

  385.                 ret = AVERROR(EINVAL);

  386.                 goto fail;

  387.             }

  388.             codec->time_base.num = avio_rb32(pb);

  389.             codec->time_base.den = avio_rb32(pb);

  390.             if (codec->time_base.num <= 0 || codec->time_base.den <= 0) {

  391.                 av_log(s, AV_LOG_ERROR, "Invalid time base %d/%d\n",

  392.                        codec->time_base.num, codec->time_base.den);

  393.                 ret = AVERROR_INVALIDDATA;

  394.                 goto fail;

  395.             }

  396.             codecpar->width = avio_rb16(pb);

  397.             codecpar->height = avio_rb16(pb);

  398.             ret = av_image_check_size(codecpar->width, codecpar->height, 0, s);

  399.             if (ret < 0)

  400.                 goto fail;

  401.             avio_rb16(pb); // gop_size

  402.             codecpar->format = avio_rb32(pb);

  403.             if (!av_pix_fmt_desc_get(codecpar->format)) {

  404.                 av_log(s, AV_LOG_ERROR, "Invalid pix fmt id: %d\n", codecpar->format);

  405.                 codecpar->format = AV_PIX_FMT_NONE;

  406.                 goto fail;

  407.             }

  408.             avio_r8(pb);   // qmin

  409.             avio_r8(pb);   // qmax

  410.             avio_r8(pb);   // max_qdiff

  411.             avio_rb16(pb); // qcompress / 10000.0

  412.             avio_rb16(pb); // qblur / 10000.0

  413.             avio_rb32(pb); // bit_rate_tolerance

  414.             avio_get_str(pb, INT_MAX, rc_eq_buf, sizeof(rc_eq_buf));

  415. 

  416.             avio_rb32(pb); // rc_max_rate

  417.             avio_rb32(pb); // rc_min_rate

  418.             avio_rb32(pb); // rc_buffer_size

  419.             avio_rb64(pb); // i_quant_factor

  420.             avio_rb64(pb); // b_quant_factor

  421.             avio_rb64(pb); // i_quant_offset

  422.             avio_rb64(pb); // b_quant_offset

  423.             avio_rb32(pb); // dct_algo

  424.             avio_rb32(pb); // strict_std_compliance

  425.             avio_rb32(pb); // max_b_frames

  426.             avio_rb32(pb); // mpeg_quant

  427.             avio_rb32(pb); // intra_dc_precision

  428.             avio_rb32(pb); // me_method

  429.             avio_rb32(pb); // mb_decision

  430.             avio_rb32(pb); // nsse_weight

  431.             avio_rb32(pb); // frame_skip_cmp

  432.             avio_rb64(pb); // rc_buffer_aggressivity

  433.             codecpar->codec_tag = avio_rb32(pb);

  434.             avio_r8(pb);   // thread_count

  435.             avio_rb32(pb); // coder_type

  436.             avio_rb32(pb); // me_cmp

  437.             avio_rb32(pb); // me_subpel_quality

  438.             avio_rb32(pb); // me_range

  439.             avio_rb32(pb); // keyint_min

  440.             avio_rb32(pb); // scenechange_threshold

  441.             avio_rb32(pb); // b_frame_strategy

  442.             avio_rb64(pb); // qcompress

  443.             avio_rb64(pb); // qblur

  444.             avio_rb32(pb); // max_qdiff

  445.             avio_rb32(pb); // refs

  446.             break;

  447.         case MKBETAG('S', 'T', 'A', 'U'):

  448.             if (f_stau++ || codecpar->codec_type != AVMEDIA_TYPE_AUDIO) {

  449.                 ret = AVERROR(EINVAL);

  450.                 goto fail;

  451.             }

  452.             codecpar->sample_rate = avio_rb32(pb);

  453.             VALIDATE_PARAMETER(sample_rate, "sample rate",        codecpar->sample_rate < 0)

  454.             codecpar->channels = avio_rl16(pb);

  455.             VALIDATE_PARAMETER(channels,    "number of channels", codecpar->channels < 0)

  456.             codecpar->frame_size = avio_rl16(pb);

  457.             VALIDATE_PARAMETER(frame_size,  "frame size",         codecpar->frame_size < 0)

  458.             break;

  459.         case MKBETAG('C', 'P', 'R', 'V'):

  460.             if (f_cprv++) {

  461.                 ret = AVERROR(EINVAL);

  462.                 goto fail;

  463.             }

  464.             enc = avcodec_find_encoder(codecpar->codec_id);

  465.             if (enc && enc->priv_data_size && enc->priv_class) {

  466.                 buffer = av_malloc(size + 1);

  467.                 if (!buffer) {

  468.                     ret = AVERROR(ENOMEM);

  469.                     goto fail;

  470.                 }

  471.                 avio_get_str(pb, size, buffer, size + 1);

  472.                 if ((ret = ffm_append_recommended_configuration(st, &buffer)) < 0)

  473.                     goto fail;

  474.             }

  475.             break;

  476.         case MKBETAG('S', '2', 'V', 'I'):

  477.             if (f_stvi++ || !size || codecpar->codec_type != AVMEDIA_TYPE_VIDEO) {

  478.                 ret = AVERROR(EINVAL);

  479.                 goto fail;

  480.             }

  481.             buffer = av_malloc(size);

  482.             if (!buffer) {

  483.                 ret = AVERROR(ENOMEM);

  484.                 goto fail;

  485.             }

  486.             avio_get_str(pb, INT_MAX, buffer, size);

  487.             // The lack of AVOptions support in AVCodecParameters makes this back and forth copying needed

  488.             avcodec_parameters_to_context(dummy_codec, codecpar);

  489.             av_set_options_string(dummy_codec, buffer, "=", ",");

  490.             avcodec_parameters_from_context(codecpar, dummy_codec);

  491.             if ((ret = ffm_append_recommended_configuration(st, &buffer)) < 0)

  492.                 goto fail;

  493.             break;

  494.         case MKBETAG('S', '2', 'A', 'U'):

  495.             if (f_stau++ || !size || codecpar->codec_type != AVMEDIA_TYPE_AUDIO) {

  496.                 ret = AVERROR(EINVAL);

  497.                 goto fail;

  498.             }

  499.             buffer = av_malloc(size);

  500.             if (!buffer) {

  501.                 ret = AVERROR(ENOMEM);

  502.                 goto fail;

  503.             }

  504.             avio_get_str(pb, INT_MAX, buffer, size);

  505.             // The lack of AVOptions support in AVCodecParameters makes this back and forth copying needed

  506.             avcodec_parameters_to_context(dummy_codec, codecpar);

  507.             av_set_options_string(dummy_codec, buffer, "=", ",");

  508.             avcodec_parameters_from_context(codecpar, dummy_codec);

  509.             if ((ret = ffm_append_recommended_configuration(st, &buffer)) < 0)

  510.                 goto fail;

  511.             break;

  512.         }

  513.         avio_seek(pb, next, SEEK_SET);

  514.     }

  515. 

  516.     /* get until end of block reached */

  517.     while ((avio_tell(pb) % ffm->packet_size) != 0 && !pb->eof_reached)

  518.         avio_r8(pb);

  519. 

  520.     /* init packet demux */

  521.     ffm->packet_ptr = ffm->packet;

  522.     ffm->packet_end = ffm->packet;

  523.     ffm->frame_offset = 0;

  524.     ffm->dts = 0;

  525.     ffm->read_state = READ_HEADER;

  526.     ffm->first_packet = 1;

  527.     avcodec_free_context(&dummy_codec);

  528.     return 0;

  529.  fail:

  530.     avcodec_free_context(&dummy_codec);

  531.     return ret;

  532. }

  533. 

  534. static int ffm_read_header(AVFormatContext *s)

  535. {

  536.     FFMContext *ffm = s->priv_data;

  537.     AVStream *st;

  538.     AVIOContext *pb = s->pb;

  539.     AVCodecContext *codec, *dummy_codec = NULL;

  540.     AVCodecParameters *codecpar;

  541.     const AVCodecDescriptor *codec_desc;

  542.     int i, nb_streams, ret;

  543.     uint32_t tag;

  544. 

  545.     /* header */

  546.     tag = avio_rl32(pb);

  547.     if (tag == MKTAG('F', 'F', 'M', '2'))

  548.         return ffm2_read_header(s);

  549.     if (tag != MKTAG('F', 'F', 'M', '1'))

  550.         goto fail;

  551.     ffm->packet_size = avio_rb32(pb);

  552.     if (ffm->packet_size != FFM_PACKET_SIZE)

  553.         goto fail;

  554.     ffm->write_index = avio_rb64(pb);

  555.     /* get also filesize */

  556.     if (pb->seekable) {

  557.         ffm->file_size = avio_size(pb);

  558.         if (ffm->write_index && 0)

  559.             adjust_write_index(s);

  560.     } else {

  561.         ffm->file_size = (UINT64_C(1) << 63) - 1;

  562.     }

  563.     dummy_codec = avcodec_alloc_context3(NULL);

  564. 

  565.     nb_streams = avio_rb32(pb);

  566.     avio_rb32(pb); /* total bitrate */

  567.     /* read each stream */

  568.     for(i=0;i<nb_streams;i++) {

  569.         char rc_eq_buf[128];

  570. 

  571.         st = avformat_new_stream(s, NULL);

  572.         if (!st)

  573.             goto fail;

  574. 

  575.         avpriv_set_pts_info(st, 64, 1, 1000000);

  576. 

  577.         codec = st->codec;

  578.         codecpar = st->codecpar;

  579.         /* generic info */

  580.         codecpar->codec_id = avio_rb32(pb);

  581.         codec_desc = avcodec_descriptor_get(codecpar->codec_id);

  582.         if (!codec_desc) {

  583.             av_log(s, AV_LOG_ERROR, "Invalid codec id: %d\n", codecpar->codec_id);

  584.             codecpar->codec_id = AV_CODEC_ID_NONE;

  585.             goto fail;

  586.         }

  587.         codecpar->codec_type = avio_r8(pb); /* codec_type */

  588.         if (codecpar->codec_type != codec_desc->type) {

  589.             av_log(s, AV_LOG_ERROR, "Codec type mismatch: expected %d, found %d\n",

  590.                    codec_desc->type, codecpar->codec_type);

  591.             codecpar->codec_id = AV_CODEC_ID_NONE;

  592.             codecpar->codec_type = AVMEDIA_TYPE_UNKNOWN;

  593.             goto fail;

  594.         }

  595.         codecpar->bit_rate = avio_rb32(pb);

  596.         if (codecpar->bit_rate < 0) {

  597.             av_log(codec, AV_LOG_WARNING, "Invalid bit rate %"PRId64"\n", codecpar->bit_rate);

  598.             goto fail;

  599.         }

  600.         codec->flags = avio_rb32(pb);

  601.         codec->flags2 = avio_rb32(pb);

  602.         codec->debug = avio_rb32(pb);

  603.         /* specific info */

  604.         switch(codecpar->codec_type) {

  605.         case AVMEDIA_TYPE_VIDEO:

  606.             codec->time_base.num = avio_rb32(pb);

  607.             codec->time_base.den = avio_rb32(pb);

  608.             if (codec->time_base.num <= 0 || codec->time_base.den <= 0) {

  609.                 av_log(s, AV_LOG_ERROR, "Invalid time base %d/%d\n",

  610.                        codec->time_base.num, codec->time_base.den);

  611.                 goto fail;

  612.             }

  613.             codecpar->width = avio_rb16(pb);

  614.             codecpar->height = avio_rb16(pb);

  615.             if (av_image_check_size(codecpar->width, codecpar->height, 0, s) < 0)

  616.                 goto fail;

  617.             avio_rb16(pb); // gop_size

  618.             codecpar->format = avio_rb32(pb);

  619.             if (!av_pix_fmt_desc_get(codecpar->format)) {

  620.                 av_log(s, AV_LOG_ERROR, "Invalid pix fmt id: %d\n", codecpar->format);

  621.                 codecpar->format = AV_PIX_FMT_NONE;

  622.                 goto fail;

  623.             }

  624.             avio_r8(pb);   // qmin

  625.             avio_r8(pb);   // qmax

  626.             avio_r8(pb);   // max_qdiff

  627.             avio_rb16(pb); // qcompress / 10000.0

  628.             avio_rb16(pb); // qblur / 10000.0

  629.             avio_rb32(pb); // bit_rate_tolerance

  630.             avio_get_str(pb, INT_MAX, rc_eq_buf, sizeof(rc_eq_buf));

  631. 

  632.             avio_rb32(pb); // rc_max_rate

  633.             avio_rb32(pb); // rc_min_rate

  634.             avio_rb32(pb); // rc_buffer_size

  635.             avio_rb64(pb); // i_quant_factor

  636.             avio_rb64(pb); // b_quant_factor

  637.             avio_rb64(pb); // i_quant_offset

  638.             avio_rb64(pb); // b_quant_offset

  639.             avio_rb32(pb); // dct_algo

  640.             avio_rb32(pb); // strict_std_compliance

  641.             avio_rb32(pb); // max_b_frames

  642.             avio_rb32(pb); // mpeg_quant

  643.             avio_rb32(pb); // intra_dc_precision

  644.             avio_rb32(pb); // me_method

  645.             avio_rb32(pb); // mb_decision

  646.             avio_rb32(pb); // nsse_weight

  647.             avio_rb32(pb); // frame_skip_cmp

  648.             avio_rb64(pb); // rc_buffer_aggressivity

  649.             codecpar->codec_tag = avio_rb32(pb);

  650.             avio_r8(pb);   // thread_count

  651.             avio_rb32(pb); // coder_type

  652.             avio_rb32(pb); // me_cmp

  653.             avio_rb32(pb); // me_subpel_quality

  654.             avio_rb32(pb); // me_range

  655.             avio_rb32(pb); // keyint_min

  656.             avio_rb32(pb); // scenechange_threshold

  657.             avio_rb32(pb); // b_frame_strategy

  658.             avio_rb64(pb); // qcompress

  659.             avio_rb64(pb); // qblur

  660.             avio_rb32(pb); // max_qdiff

  661.             avio_rb32(pb); // refs

  662.             break;

  663.         case AVMEDIA_TYPE_AUDIO:

  664.             codecpar->sample_rate = avio_rb32(pb);

  665.             VALIDATE_PARAMETER(sample_rate, "sample rate",        codecpar->sample_rate < 0)

  666.             codecpar->channels = avio_rl16(pb);

  667.             VALIDATE_PARAMETER(channels,    "number of channels", codecpar->channels < 0)

  668.             codecpar->frame_size = avio_rl16(pb);

  669.             VALIDATE_PARAMETER(frame_size,  "frame size",         codecpar->frame_size < 0)

  670.             break;

  671.         default:

  672.             goto fail;

  673.         }

  674.         if (codec->flags & AV_CODEC_FLAG_GLOBAL_HEADER) {

  675.             int size = avio_rb32(pb);

  676.             if (size < 0 || size >= FF_MAX_EXTRADATA_SIZE) {

  677.                 av_log(s, AV_LOG_ERROR, "Invalid extradata size %d\n", size);

  678.                 goto fail;

  679.             }

  680.             codecpar->extradata = av_mallocz(size + AV_INPUT_BUFFER_PADDING_SIZE);

  681.             if (!codecpar->extradata)

  682.                 return AVERROR(ENOMEM);

  683.             codecpar->extradata_size = size;

  684.             avio_read(pb, codecpar->extradata, size);

  685.         }

  686.     }

  687. 

  688.     /* get until end of block reached */

  689.     while ((avio_tell(pb) % ffm->packet_size) != 0 && !pb->eof_reached)

  690.         avio_r8(pb);

  691. 

  692.     /* init packet demux */

  693.     ffm->packet_ptr = ffm->packet;

  694.     ffm->packet_end = ffm->packet;

  695.     ffm->frame_offset = 0;

  696.     ffm->dts = 0;

  697.     ffm->read_state = READ_HEADER;

  698.     ffm->first_packet = 1;

  699.     avcodec_free_context(&dummy_codec);

  700.     return 0;

  701.  fail:

  702.     avcodec_free_context(&dummy_codec);

  703.     return -1;

  704. }

  705. 

  706. /* return < 0 if eof */

  707. static int ffm_read_packet(AVFormatContext *s, AVPacket *pkt)

  708. {

  709.     int size;

  710.     FFMContext *ffm = s->priv_data;

  711.     int duration, ret;

  712. 

  713.     switch(ffm->read_state) {

  714.     case READ_HEADER:

  715.         if ((ret = ffm_is_avail_data(s, FRAME_HEADER_SIZE+4)) < 0)

  716.             return ret;

  717. 

  718.         ff_dlog(s, "pos=%08"PRIx64" spos=%"PRIx64", write_index=%"PRIx64" size=%"PRIx64"\n",

  719.                avio_tell(s->pb), s->pb->pos, ffm->write_index, ffm->file_size);

  720.         if (ffm_read_data(s, ffm->header, FRAME_HEADER_SIZE, 1) !=

  721.             FRAME_HEADER_SIZE)

  722.             return -1;

  723.         if (ffm->header[1] & FLAG_DTS)

  724.             if (ffm_read_data(s, ffm->header+16, 4, 1) != 4)

  725.                 return -1;

  726.         ffm->read_state = READ_DATA;

  727.         /* fall through */

  728.     case READ_DATA:

  729.         size = AV_RB24(ffm->header + 2);

  730.         if ((ret = ffm_is_avail_data(s, size)) < 0)

  731.             return ret;

  732. 

  733.         duration = AV_RB24(ffm->header + 5);

  734. 

  735.         if (av_new_packet(pkt, size) < 0) {

  736.             return AVERROR(ENOMEM);

  737.         }

  738.         pkt->stream_index = ffm->header[0];

  739.         if ((unsigned)pkt->stream_index >= s->nb_streams) {

  740.             av_log(s, AV_LOG_ERROR, "invalid stream index %d\n", pkt->stream_index);

  741.             av_packet_unref(pkt);

  742.             ffm->read_state = READ_HEADER;

  743.             return -1;

  744.         }

  745.         pkt->pos = avio_tell(s->pb);

  746.         if (ffm->header[1] & FLAG_KEY_FRAME)

  747.             pkt->flags |= AV_PKT_FLAG_KEY;

  748. 

  749.         ffm->read_state = READ_HEADER;

  750.         if (ffm_read_data(s, pkt->data, size, 0) != size) {

  751.             /* bad case: desynchronized packet. we cancel all the packet loading */

  752.             av_packet_unref(pkt);

  753.             return -1;

  754.         }

  755.         pkt->pts = AV_RB64(ffm->header+8);

  756.         if (ffm->header[1] & FLAG_DTS)

  757.             pkt->dts = pkt->pts - AV_RB32(ffm->header+16);

  758.         else

  759.             pkt->dts = pkt->pts;

  760.         pkt->duration = duration;

  761.         break;

  762.     }

  763.     return 0;

  764. }

  765. 

  766. /* seek to a given time in the file. The file read pointer is

  767.    positioned at or before pts. XXX: the following code is quite

  768.    approximative */

  769. static int ffm_seek(AVFormatContext *s, int stream_index, int64_t wanted_pts, int flags)

  770. {

  771.     FFMContext *ffm = s->priv_data;

  772.     int64_t pos_min, pos_max, pos;

  773.     int64_t pts_min, pts_max, pts;

  774.     double pos1;

  775. 

  776.     ff_dlog(s, "wanted_pts=%0.6f\n", wanted_pts / 1000000.0);

  777.     /* find the position using linear interpolation (better than

  778.        dichotomy in typical cases) */

  779.     if (ffm->write_index && ffm->write_index < ffm->file_size) {

  780.         if (get_dts(s, FFM_PACKET_SIZE) < wanted_pts) {

  781.             pos_min = FFM_PACKET_SIZE;

  782.             pos_max = ffm->write_index - FFM_PACKET_SIZE;

  783.         } else {

  784.             pos_min = ffm->write_index;

  785.             pos_max = ffm->file_size - FFM_PACKET_SIZE;

  786.         }

  787.     } else {

  788.         pos_min = FFM_PACKET_SIZE;

  789.         pos_max = ffm->file_size - FFM_PACKET_SIZE;

  790.     }

  791.     while (pos_min <= pos_max) {

  792.         pts_min = get_dts(s, pos_min);

  793.         pts_max = get_dts(s, pos_max);

  794.         if (pts_min > wanted_pts || pts_max <= wanted_pts) {

  795.             pos = pts_min > wanted_pts ? pos_min : pos_max;

  796.             goto found;

  797.         }

  798.         /* linear interpolation */

  799.         pos1 = (double)(pos_max - pos_min) * (double)(wanted_pts - pts_min) /

  800.             (double)(pts_max - pts_min);

  801.         pos = (((int64_t)pos1) / FFM_PACKET_SIZE) * FFM_PACKET_SIZE;

  802.         if (pos <= pos_min)

  803.             pos = pos_min;

  804.         else if (pos >= pos_max)

  805.             pos = pos_max;

  806.         pts = get_dts(s, pos);

  807.         /* check if we are lucky */

  808.         if (pts == wanted_pts) {

  809.             goto found;

  810.         } else if (pts > wanted_pts) {

  811.             pos_max = pos - FFM_PACKET_SIZE;

  812.         } else {

  813.             pos_min = pos + FFM_PACKET_SIZE;

  814.         }

  815.     }

  816.     pos = (flags & AVSEEK_FLAG_BACKWARD) ? pos_min : pos_max;

  817. 

  818.  found:

  819.     if (ffm_seek1(s, pos) < 0)

  820.         return -1;

  821. 

  822.     /* reset read state */

  823.     ffm->read_state = READ_HEADER;

  824.     ffm->packet_ptr = ffm->packet;

  825.     ffm->packet_end = ffm->packet;

  826.     ffm->first_packet = 1;

  827. 

  828.     return 0;

  829. }

  830. 

  831. static int ffm_probe(AVProbeData *p)

  832. {

  833.     if (

  834.         p->buf[0] == 'F' && p->buf[1] == 'F' && p->buf[2] == 'M' &&

  835.         (p->buf[3] == '1' || p->buf[3] == '2'))

  836.         return AVPROBE_SCORE_MAX + 1;

  837.     return 0;

  838. }

  839. 

  840. static const AVOption options[] = {

  841.     {"server_attached", NULL, offsetof(FFMContext, server_attached), AV_OPT_TYPE_BOOL, {.i64 = 0}, 0, 1, AV_OPT_FLAG_EXPORT },

  842.     {"ffm_write_index", NULL, offsetof(FFMContext, write_index), AV_OPT_TYPE_INT64, {.i64 = 0}, 0, INT64_MAX, AV_OPT_FLAG_EXPORT },

  843.     {"ffm_file_size", NULL, offsetof(FFMContext, file_size), AV_OPT_TYPE_INT64, {.i64 = 0}, 0, INT64_MAX, AV_OPT_FLAG_EXPORT },

  844.     { NULL },

  845. };

  846. 

  847. static const AVClass ffm_class = {

  848.     .class_name = "ffm demuxer",

  849.     .item_name  = av_default_item_name,

  850.     .option     = options,

  851.     .version    = LIBAVUTIL_VERSION_INT,

  852. };

  853. AVInputFormat ff_ffm_demuxer = {

  854.     .name           = "ffm",

  855.     .long_name      = NULL_IF_CONFIG_SMALL("FFM (FFserver live feed)"),

  856.     .priv_data_size = sizeof(FFMContext),

  857.     .read_probe     = ffm_probe,

  858.     .read_header    = ffm_read_header,

  859.     .read_packet    = ffm_read_packet,

  860.     .read_seek      = ffm_seek,

  861.     .priv_class     = &ffm_class,

  862. };