3 * Copyright (c) 2003 Charles Yates
5 * This file is part of FFmpeg.
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.
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.
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
25 #include <sys/types.h>
28 #include "libavutil/avstring.h"
29 #include "libavformat/framehook.h"
30 #include "libavformat/avformat.h"
31 #include "libswscale/swscale.h"
34 static int sws_flags = SWS_BICUBIC;
36 /** Bi-directional pipe structure.
47 /** Create a bidirectional pipe for the given command.
50 static rwpipe *rwpipe_open( int argc, char *argv[] )
52 rwpipe *this = av_mallocz( sizeof( rwpipe ) );
66 #define COMMAND_SIZE 10240
67 char *command = av_mallocz( COMMAND_SIZE );
70 strcpy( command, "" );
71 for ( i = 0; i < argc; i ++ )
73 av_strlcat( command, argv[ i ], COMMAND_SIZE );
74 av_strlcat( command, " ", COMMAND_SIZE );
77 dup2( output[ 0 ], STDIN_FILENO );
78 dup2( input[ 1 ], STDOUT_FILENO );
85 execl("/bin/sh", "sh", "-c", command, (char*)NULL );
93 this->reader = fdopen( input[ 0 ], "r" );
94 this->writer = fdopen( output[ 1 ], "w" );
101 /** Read data from the pipe.
104 static FILE *rwpipe_reader( rwpipe *this )
112 /** Write data to the pipe.
115 static FILE *rwpipe_writer( rwpipe *this )
123 /* Read a number from the pipe - assumes PNM style headers.
126 static int rwpipe_read_number( rwpipe *rw )
130 FILE *in = rwpipe_reader( rw );
136 while( c != EOF && !isdigit( c ) && c != '#' )
140 while( c != EOF && c != '\n' )
143 while ( c != EOF && !isdigit( c ) );
145 while( c != EOF && isdigit( c ) )
147 value = value * 10 + ( c - '0' );
154 /** Read a PPM P6 header.
157 static int rwpipe_read_ppm_header( rwpipe *rw, int *width, int *height )
160 FILE *in = rwpipe_reader( rw );
163 fgets( line, 3, in );
164 if ( !strncmp( line, "P6", 2 ) )
166 *width = rwpipe_read_number( rw );
167 *height = rwpipe_read_number( rw );
168 max = rwpipe_read_number( rw );
169 return max != 255 || *width <= 0 || *height <= 0;
174 /** Close the pipe and process.
177 static void rwpipe_close( rwpipe *this )
181 fclose( this->reader );
182 fclose( this->writer );
183 waitpid( this->pid, NULL, 0 );
188 /** Context info for this vhook - stores the pipe and image buffers.
199 // This vhook first converts frame to RGB ...
200 struct SwsContext *toRGB_convert_ctx;
201 // ... then processes it via a PPM command pipe ...
202 // ... and finally converts back frame from RGB to initial format
203 struct SwsContext *fromRGB_convert_ctx;
207 /** Initialise the context info for this vhook.
210 int Configure(void **ctxp, int argc, char *argv[])
214 *ctxp = av_mallocz(sizeof(ContextInfo));
215 if ( *ctxp != NULL && argc > 1 )
217 ContextInfo *info = (ContextInfo *)*ctxp;
218 info->rw = rwpipe_open( argc - 1, &argv[ 1 ] );
228 void Process(void *ctx, AVPicture *picture, enum PixelFormat pix_fmt, int width, int height, int64_t pts)
231 ContextInfo *ci = (ContextInfo *) ctx;
234 AVPicture *pict = picture;
239 FILE *in = rwpipe_reader( ci->rw );
240 FILE *out = rwpipe_writer( ci->rw );
242 /* Check that we have a pipe to talk to. */
243 if ( in == NULL || out == NULL )
246 /* Convert to RGB24 if necessary */
247 if ( !err && pix_fmt != PIX_FMT_RGB24 )
249 int size = avpicture_get_size(PIX_FMT_RGB24, width, height);
251 if ( size != ci->size1 )
254 ci->buf1 = av_malloc(size);
256 err = ci->buf1 == NULL;
261 avpicture_fill(&picture1, ci->buf1, PIX_FMT_RGB24, width, height);
263 // if we already got a SWS context, let's realloc if is not re-useable
264 ci->toRGB_convert_ctx = sws_getCachedContext(ci->toRGB_convert_ctx,
265 width, height, pix_fmt,
266 width, height, PIX_FMT_RGB24,
267 sws_flags, NULL, NULL, NULL);
268 if (ci->toRGB_convert_ctx == NULL) {
269 av_log(NULL, AV_LOG_ERROR,
270 "Cannot initialize the toRGB conversion context\n");
274 // img_convert parameters are 2 first destination, then 4 source
275 // sws_scale parameters are context, 4 first source, then 2 destination
276 sws_scale(ci->toRGB_convert_ctx,
277 picture->data, picture->linesize, 0, height,
278 picture1.data, picture1.linesize);
284 /* Write out the PPM */
287 ptr = pict->data[ 0 ];
288 fprintf( out, "P6\n%d %d\n255\n", width, height );
289 for ( i = 0; !err && i < height; i ++ )
291 err = !fwrite( ptr, width * 3, 1, out );
292 ptr += pict->linesize[ 0 ];
298 /* Read the PPM returned. */
299 if ( !err && !rwpipe_read_ppm_header( ci->rw, &out_width, &out_height ) )
301 int size = avpicture_get_size(PIX_FMT_RGB24, out_width, out_height);
303 if ( size != ci->size2 )
306 ci->buf2 = av_malloc(size);
308 err = ci->buf2 == NULL;
313 avpicture_fill(&picture2, ci->buf2, PIX_FMT_RGB24, out_width, out_height);
314 ptr = picture2.data[ 0 ];
315 for ( i = 0; !err && i < out_height; i ++ )
317 err = !fread( ptr, out_width * 3, 1, in );
318 ptr += picture2.linesize[ 0 ];
323 /* Convert the returned PPM back to the input format */
326 /* The out_width/out_height returned from the PPM
327 * filter won't necessarily be the same as width and height
328 * but it will be scaled anyway to width/height.
330 av_log(NULL, AV_LOG_DEBUG,
331 "PPM vhook: Input dimensions: %d x %d Output dimensions: %d x %d\n",
332 width, height, out_width, out_height);
333 ci->fromRGB_convert_ctx = sws_getCachedContext(ci->fromRGB_convert_ctx,
334 out_width, out_height, PIX_FMT_RGB24,
335 width, height, pix_fmt,
336 sws_flags, NULL, NULL, NULL);
337 if (ci->fromRGB_convert_ctx == NULL) {
338 av_log(NULL, AV_LOG_ERROR,
339 "Cannot initialize the fromRGB conversion context\n");
343 // img_convert parameters are 2 first destination, then 4 source
344 // sws_scale parameters are context, 4 first source, then 2 destination
345 sws_scale(ci->fromRGB_convert_ctx,
346 picture2.data, picture2.linesize, 0, out_height,
347 picture->data, picture->linesize);
351 /** Clean up the effect.
354 void Release(void *ctx)
357 ci = (ContextInfo *) ctx;
361 rwpipe_close( ci->rw );
364 sws_freeContext(ci->toRGB_convert_ctx);
365 sws_freeContext(ci->fromRGB_convert_ctx);