1 /*****************************************************************************
2 * y4m.c: x264 y4m input module
3 *****************************************************************************
4 * Copyright (C) 2003-2009 x264 project
6 * Authors: Laurent Aimar <fenrir@via.ecp.fr>
7 * Loren Merritt <lorenm@u.washington.edu>
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02111, USA.
22 *****************************************************************************/
31 int seq_header_len, frame_header_len;
35 #define Y4M_MAGIC "YUV4MPEG2"
36 #define MAX_YUV4_HEADER 80
37 #define Y4M_FRAME_MAGIC "FRAME"
38 #define MAX_FRAME_HEADER 80
40 static int open_file( char *psz_filename, hnd_t *p_handle, video_info_t *info, cli_input_opt_t *opt )
42 y4m_hnd_t *h = malloc( sizeof(y4m_hnd_t) );
44 char header[MAX_YUV4_HEADER+10];
45 char *tokstart, *tokend, *header_end;
52 if( !strcmp( psz_filename, "-" ) )
55 h->fh = fopen(psz_filename, "rb");
59 h->frame_header_len = strlen( Y4M_FRAME_MAGIC )+1;
62 for( i = 0; i < MAX_YUV4_HEADER; i++ )
64 header[i] = fgetc( h->fh );
65 if( header[i] == '\n' )
67 /* Add a space after last option. Makes parsing "444" vs
74 if( i == MAX_YUV4_HEADER || strncmp( header, Y4M_MAGIC, strlen( Y4M_MAGIC ) ) )
78 header_end = &header[i+1]; /* Include space */
79 h->seq_header_len = i+1;
80 for( tokstart = &header[strlen( Y4M_MAGIC )+1]; tokstart < header_end; tokstart++ )
82 if( *tokstart == 0x20 )
86 case 'W': /* Width. Required. */
87 h->width = info->width = strtol( tokstart, &tokend, 10 );
90 case 'H': /* Height. Required. */
91 h->height = info->height = strtol( tokstart, &tokend, 10 );
94 case 'C': /* Color space */
95 if( strncmp( "420", tokstart, 3 ) )
97 fprintf( stderr, "y4m [error]: colorspace unhandled\n" );
100 tokstart = strchr( tokstart, 0x20 );
102 case 'I': /* Interlace type */
103 switch( *tokstart++ )
111 info->interlaced = 1;
114 case 'F': /* Frame rate - 0:0 if unknown */
115 if( sscanf( tokstart, "%d:%d", &n, &d ) == 2 && n && d )
117 x264_reduce_fraction( &n, &d );
121 tokstart = strchr( tokstart, 0x20 );
123 case 'A': /* Pixel aspect - 0:0 if unknown */
124 /* Don't override the aspect ratio if sar has been explicitly set on the commandline. */
125 if( sscanf( tokstart, "%d:%d", &n, &d ) == 2 && n && d )
127 x264_reduce_fraction( &n, &d );
129 info->sar_height = d;
131 tokstart = strchr( tokstart, 0x20 );
133 case 'X': /* Vendor extensions */
134 if( !strncmp( "YSCSS=", tokstart, 6 ) )
136 /* Older nonstandard pixel format representation */
138 if( strncmp( "420JPEG",tokstart, 7 ) &&
139 strncmp( "420MPEG2",tokstart, 8 ) &&
140 strncmp( "420PALDV",tokstart, 8 ) )
142 fprintf( stderr, "y4m [error]: unsupported extended colorspace\n" );
146 tokstart = strchr( tokstart, 0x20 );
155 /* Most common case: frame_header = "FRAME" */
156 static int get_frame_total( hnd_t handle )
158 y4m_hnd_t *h = handle;
159 int i_frame_total = 0;
161 if( x264_is_regular_file( h->fh ) )
163 uint64_t init_pos = ftell( h->fh );
164 fseek( h->fh, 0, SEEK_END );
165 uint64_t i_size = ftell( h->fh );
166 fseek( h->fh, init_pos, SEEK_SET );
167 i_frame_total = (int)((i_size - h->seq_header_len) /
168 (3*(h->width*h->height)/2+h->frame_header_len));
171 return i_frame_total;
174 static int read_frame_internal( x264_picture_t *p_pic, y4m_hnd_t *h )
176 int slen = strlen( Y4M_FRAME_MAGIC );
180 /* Read frame header - without terminating '\n' */
181 if( fread( header, 1, slen, h->fh ) != slen )
185 if( strncmp( header, Y4M_FRAME_MAGIC, slen ) )
187 fprintf( stderr, "y4m [error]: bad header magic (%"PRIx32" <=> %s)\n",
188 M32(header), header );
192 /* Skip most of it */
193 while( i < MAX_FRAME_HEADER && fgetc( h->fh ) != '\n' )
195 if( i == MAX_FRAME_HEADER )
197 fprintf( stderr, "y4m [error]: bad frame header!\n" );
200 h->frame_header_len = i+slen+1;
202 if( fread( p_pic->img.plane[0], h->width * h->height, 1, h->fh ) <= 0
203 || fread( p_pic->img.plane[1], h->width * h->height / 4, 1, h->fh ) <= 0
204 || fread( p_pic->img.plane[2], h->width * h->height / 4, 1, h->fh ) <= 0 )
210 static int read_frame( x264_picture_t *p_pic, hnd_t handle, int i_frame )
212 y4m_hnd_t *h = handle;
214 if( i_frame > h->next_frame )
216 if( x264_is_regular_file( h->fh ) )
217 fseek( h->fh, (uint64_t)i_frame*(3*(h->width*h->height)/2+h->frame_header_len)
218 + h->seq_header_len, SEEK_SET );
220 while( i_frame > h->next_frame )
222 if( read_frame_internal( p_pic, h ) )
228 if( read_frame_internal( p_pic, h ) )
231 h->next_frame = i_frame+1;
235 static int close_file( hnd_t handle )
237 y4m_hnd_t *h = handle;
245 cli_input_t y4m_input = { open_file, get_frame_total, x264_picture_alloc, read_frame, NULL, x264_picture_clean, close_file };