libmpcodecs/vd_zrmjpeg.c

   1 /*
   2  * Copyright (C) 2005 Rik Snel <rsnel@cube.dyndns.org>, license GPL v2 or later
   3  * - based on vd_mpegpes.c by A'rpi (C) 2002-2003
   4  * - guess_mjpeg_type code stolen from lav_io.c (C) 2000 Rainer Johanni
   5  *   <Rainer@Johanni.de> from the mjpegtools package
   6  */
   7 #include <stdio.h>
   8 #include <stdlib.h>
   9
  10 #include "config.h"
  11 #include "mp_msg.h"
  12 #include "vfcap.h"
  13
  14 /* some convenient #define's, is this portable enough? */
  15 #define VERBOSE(...) mp_msg(MSGT_DECVIDEO, MSGL_V, "vd_zrmjpeg: " __VA_ARGS__)
  16 #define ERROR(...) mp_msg(MSGT_DECVIDEO, MSGL_ERR, "vd_zrmjpeg: " __VA_ARGS__)
  17 #define WARNING(...) mp_msg(MSGT_DECVIDEO, MSGL_WARN, \
  18                 "vd_zrmjpeg: " __VA_ARGS__)
  19
  20 #include "vd_internal.h"
  21
  22 static vd_info_t info =
  23 {
  24         "Zoran MJPEG Video passthrough",
  25         "zrmjpeg",
  26         "Rik Snel <snel@phys.uu.nl>",
  27         "Rik Snel <snel@phys.uu.nl>",
  28         "for hw decoders (DC10(+)/buz/lml33)"
  29 };
  30
  31 LIBVD_EXTERN(zrmjpeg)
  32
  33 #include "libvo/video_out.h"
  34
  35 typedef struct {
  36         int vo_inited;
  37         unsigned int preferred_csp;
  38 } vd_zrmjpeg_ctx_t;
  39
  40 static int query_format(sh_video_t *sh, unsigned int format) {
  41         vd_zrmjpeg_ctx_t *ctx = sh->context;
  42         if (format == ctx->preferred_csp) return VFCAP_CSP_SUPPORTED;
  43         return CONTROL_FALSE;
  44 }
  45
  46 // to set/get/query special features/parameters
  47 static int control(sh_video_t *sh, int cmd, void* arg, ...) {
  48         switch (cmd) {
  49                 case VDCTRL_QUERY_FORMAT:
  50                         return query_format(sh, *((unsigned int*)arg));
  51         }
  52         return CONTROL_UNKNOWN;
  53 }
  54
  55 // init driver
  56 static int init(sh_video_t *sh) {
  57         vd_zrmjpeg_ctx_t *ctx;
  58
  59         VERBOSE("init called\n");
  60         ctx = malloc(sizeof(*ctx));
  61         if (!ctx) return 0;
  62         memset(ctx, 0, sizeof(*ctx));
  63         sh->context = ctx;
  64
  65         /* defer init of vo until the first frame is known */
  66         return 1;
  67 #if 0
  68         return mpcodecs_config_vo(sh, sh->disp_w, sh->disp_h, IMGFMT_ZRMJPEGIT);
  69 #endif
  70 }
  71
  72 // uninit driver
  73 static void uninit(sh_video_t *sh) {
  74         free(sh->context);
  75 }
  76
  77 /* parts directly stolen from scan_jpg() and lav_open_input_file */
  78 static int get_int2(unsigned char *buf) {
  79         return buf[0]*256 + buf[1];
  80 }
  81
  82 #define M_SOF0  0xC0
  83 #define M_SOF1  0xC1
  84 #define M_DHT   0xC4
  85 #define M_SOI   0xD8            /* Start Of Image (beginning of datastream) */
  86 #define M_EOI   0xD9            /* End Of Image (end of datastream) */
  87 #define M_SOS   0xDA            /* Start Of Scan (begins compressed data) */
  88 #define M_DQT   0xDB
  89 #define M_APP0  0xE0
  90 #define M_APP1  0xE1
  91 /* returns 0 in case of failure */
  92 static unsigned int guess_mjpeg_type(unsigned char *data, unsigned int size,
  93                 int d_height) {
  94         unsigned int p;
  95         int marker, length, height, ncomps, i, hf[3], vf[3];
  96         unsigned int app0 = 0, header = 0;
  97
  98         /* The initial marker must be SIO */
  99         if (size < 2) {
 100                 ERROR("JPEG data too short (%d bytes)\n", size);
 101                 return 0;
 102         }
 103
 104         if (data[0] != 0xFF || data[1] != M_SOI) {
 105                 ERROR("JPEG data must start with FFD8, but doesn't\n");
 106                 return 0;
 107         }
 108
 109         p = 2; /* pointer within jpeg data */
 110
 111         while (p < size) {
 112                 /* search 0xFF */
 113                 while(data[p] != 0xFF) {
 114                         p++;
 115                         if (p >= size) return 0;
 116                 }
 117
 118                 /* get marker code, skip duplicate FF's */
 119                 while(data[p] == 0xFF) {
 120                         p++;
 121                         if (p >= size) return 0;
 122                 }
 123
 124                 marker = data[p++];
 125
 126                 /* marker may have an associated length */
 127                 if (p <= size - 2) length = get_int2(data+p);
 128                 else length = 0;
 129
 130                 switch (marker) {
 131                         case M_SOF0:
 132                         case M_SOF1:
 133                                 header = p-2;
 134                                 VERBOSE("found offset of header %u\n",
 135                                                 header);
 136                                 break;
 137                         case M_SOS:
 138                                 size = 0;
 139                                 continue;
 140                         case M_APP0:
 141                                 app0 = p-2;
 142                                 VERBOSE("found offset of APP0 %u\n",
 143                                                 app0);
 144                                 break;
 145                 }
 146
 147                 /* these markers shouldn't have parameters,
 148                  * i.e. we don't need to skip anaything */
 149                 if (marker == 0 || marker == 1 ||
 150                                 (marker >= 0xd0 && marker < 0xd8))
 151                         continue;
 152
 153                 if  (p + length <= size) p += length;
 154                 else {
 155                         ERROR("input JPEG too short, data missing\n");
 156                         return 0;
 157                 }
 158         }
 159
 160         if (!header) {
 161                 ERROR("JPEG header (with resolution and sampling factors) not found\n");
 162                 return 0;
 163         }
 164
 165         if (data[header + 9] != 3) {
 166                 ERROR("JPEG has wrong number of components\n");
 167                 return 0;
 168         }
 169
 170         /* get the horizontal and vertical sample factors */
 171         for (i = 0; i < 3; i++) {
 172                 hf[i] = data[header + 10 + 3*i + 1]>>4;
 173                 vf[i] = data[header + 10 + 3*i + 1]&0x0F;
 174         }
 175
 176         if (hf[0] != 2 || hf[1] != 1 || hf[2] != 1 ||
 177                         vf[0] != 1 || vf[1] != 1 || vf[2] != 1) {
 178                 ERROR("JPEG has wrong internal image format\n");
 179         } else VERBOSE("JPEG has colorspace YUV422 with minimal sampling factors (good)\n");
 180
 181         height = get_int2(data + header + 5);
 182         if (height == d_height) {
 183                 VERBOSE("data is non interlaced\n");
 184                 return IMGFMT_ZRMJPEGNI;
 185         }
 186
 187         if (2*height != d_height) {
 188                 ERROR("something very inconsistent happened\n");
 189                 return 0;
 190         }
 191
 192
 193         if (app0 && get_int2(data + app0 + 2) >= 5 &&
 194                         strncasecmp((char*)(data + app0 + 4), "AVI1", 4) == 0) {
 195                 if (data[app0+8] == 1) {
 196                         VERBOSE("data is interlaced, APP0: top-first (1)\n");
 197                         return IMGFMT_ZRMJPEGIT;
 198                 } else {
 199                         VERBOSE("data is interlaced, APP0: bottom-first (%d)\n",
 200                                         data[app0+8]);
 201                         return IMGFMT_ZRMJPEGIB;
 202                 }
 203         } else {
 204                 VERBOSE("data is interlaced, no (valid) APP0 marker, "
 205                                 "guessing top-first\n");
 206                 return IMGFMT_ZRMJPEGIT;
 207         }
 208
 209
 210         return 0;
 211 }
 212
 213 // decode a frame
 214 static mp_image_t* decode(sh_video_t *sh, void* data, int len, int flags) {
 215         mp_image_t* mpi;
 216         vd_zrmjpeg_ctx_t *ctx = sh->context;
 217
 218         if (!ctx->vo_inited) {
 219                 ctx->preferred_csp = guess_mjpeg_type(data, len, sh->disp_h);
 220                 if (ctx->preferred_csp == 0) return NULL;
 221                 mpcodecs_config_vo(sh, sh->disp_w, sh->disp_h,
 222                                 ctx->preferred_csp);
 223                 ctx->vo_inited = 1;
 224         }
 225
 226         mpi = mpcodecs_get_image(sh, MP_IMGTYPE_EXPORT, 0,
 227                         sh->disp_w, sh->disp_h);
 228         /* abuse of mpi */
 229         mpi->planes[0]=(uint8_t*)data;
 230         mpi->planes[1]=(uint8_t*)len;
 231         return mpi;
 232 }