diff options
Diffstat (limited to 'libavfilter/libmpcodecs/vf_framestep.c')
| -rw-r--r-- | libavfilter/libmpcodecs/vf_framestep.c | 205 |
1 files changed, 205 insertions, 0 deletions
diff --git a/libavfilter/libmpcodecs/vf_framestep.c b/libavfilter/libmpcodecs/vf_framestep.c new file mode 100644 index 0000000000..cdf5386670 --- /dev/null +++ b/libavfilter/libmpcodecs/vf_framestep.c @@ -0,0 +1,205 @@ +/* + * filter to ouput only 1 every n frame, or only the I (key)frame + * + * The parameters are: + * + * [I] | [i]num + * + * if you call the filter with I (uppercase) as the parameter + * ... -vf framestep=I ... + * then ONLY the keyframes are outputted. + * For DVD it means, generally, one every 15 frames (IBBPBBPBBPBBPBB), for avi it means + * every scene change or every keyint value (see -lavcopts). + * + * if you call the filter with the i (lowercase) + * ... -vf framestep=i ... + * then a I! followed by a cr is printed when a key frame (eg Intra frame) is + * found, leaving the current line of mplayer/mencoder, where you got the + * time, in seconds, and frame of the key. Use this information to split the + * AVI. + * + * After the i or alone you can put a positive number and only one frame every + * x (the number you set) is passed on the filter chain, limiting the output + * of the frame. + * + * Example + * ... -vf framestep=i20 ... + * Dump one every 20 frames, printing on the console when a I-Frame is encounter. + * + * ... -vf framestep=25 + * Dump one every 25 frames. + * + * If you call the filter without parameter it does nothing (except using memory + * and resource of your system,. of course). + * + * This filter doesn' t work like the option -sstep seconds. + * + * The -sstep seek to the new position, without decoding all frames but, + * expecially on avi file coded whith mpeg4 (lavc or xvid or divx), the + * seek is not always too much precise. + * + * This filter simply discard the unwanted frames, so you are very precise in + * counting the frame but sometime you use a lot of CPU for nothing. + * + * As usual it depends on what you're doing. + * + * copyright (c) 2003 Daniele Forghieri ( guru@digitalfantasy.it ) + * + * This file is part of MPlayer. + * + * MPlayer is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * MPlayer is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License along + * with MPlayer; if not, write to the Free Software Foundation, Inc., + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. + */ + +#include <stdio.h> +#include <stdlib.h> +#include <string.h> + +#include "config.h" +#include "mp_msg.h" +#include "help_mp.h" +#include "cpudetect.h" + +#include "img_format.h" +#include "mp_image.h" +#include "vf.h" + +/* Uncomment if you want to print some info on the format */ +// #define DUMP_FORMAT_DATA + +/* Private data */ +struct vf_priv_s { + /* Current frame */ + int frame_cur; + /* Frame output step, 0 = all */ + int frame_step; + /* Only I-Frame (2), print on I-Frame (1) */ + int dump_iframe; +}; + +/* Filter handler */ +static int put_image(struct vf_instance *vf, mp_image_t *mpi, double pts) +{ + mp_image_t *dmpi; + struct vf_priv_s *priv; + int skip; + + priv = vf->priv; + + /* Print the 'I' if is a intra frame. The \n advance the current line so you got the + * current file time (in second) and the frame number on the console ;-) + */ + if (priv->dump_iframe) { + if (mpi->pict_type == 1) { + mp_msg(MSGT_VFILTER, MSGL_INFO, "I!\n"); + } + } + + /* decide if frame must be shown */ + if (priv->dump_iframe == 2) { + /* Only key frame */ + skip = mpi->pict_type == 1 ? 0 : 1; + } + else { + /* Only 1 every frame_step */ + skip = 0; + if ((priv->frame_step != 0) && ((priv->frame_cur % priv->frame_step) != 0)) { + skip = 1; + } + } + /* Increment current frame */ + ++priv->frame_cur; + + if (skip == 0) { + /* Get image, export type (we don't modify tghe image) */ + dmpi=vf_get_image(vf->next, mpi->imgfmt, + MP_IMGTYPE_EXPORT, 0, + mpi->w, mpi->h); + /* Copy only the pointer ( MP_IMGTYPE_EXPORT ! ) */ + dmpi->planes[0] = mpi->planes[0]; + dmpi->planes[1] = mpi->planes[1]; + dmpi->planes[2] = mpi->planes[2]; + + dmpi->stride[0] = mpi->stride[0]; + dmpi->stride[1] = mpi->stride[1]; + dmpi->stride[2] = mpi->stride[2]; + + dmpi->width = mpi->width; + dmpi->height = mpi->height; + + /* Chain to next filter / output ... */ + return vf_next_put_image(vf, dmpi, pts); + } + + /* Skip the frame */ + return 0; +} + +static void uninit(struct vf_instance *vf) +{ + /* Free private data */ + free(vf->priv); +} + +/* Main entry funct for the filter */ +static int vf_open(vf_instance_t *vf, char *args) +{ + struct vf_priv_s *p; + + vf->put_image = put_image; + vf->uninit = uninit; + vf->default_reqs = VFCAP_ACCEPT_STRIDE; + vf->priv = p = calloc(1, sizeof(struct vf_priv_s)); + if (p == NULL) { + return 0; + } + + if (args != NULL) { +#ifdef DUMP_FORMAT_DATA + if (*args == 'd') { + p->dump_iframe = 3; + } + else +#endif + if (*args == 'I') { + /* Dump only KEY (ie INTRA) frame */ + p->dump_iframe = 2; + } + else { + if (*args == 'i') { + /* Print a 'I!' when a i-frame is encounter */ + p->dump_iframe = 1; + ++args; + } + + if (*args != '\0') { + p->frame_step = atoi(args); + if (p->frame_step <= 0) { + mp_msg(MSGT_VFILTER, MSGL_WARN, MSGTR_MPCODECS_ErrorParsingArgument); + return 0; + } + } + } + } + return 1; +} + +const vf_info_t vf_info_framestep = { + "Dump one every n / key frames", + "framestep", + "Daniele Forghieri", + "", + vf_open, + NULL +}; |