FFmpeg
aliaspixenc.c
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1 /*
2  * Alias PIX image encoder
3  * Copyright (C) 2014 Vittorio Giovara <vittorio.giovara@gmail.com>
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 "libavutil/intreadwrite.h"
23 
24 #include "avcodec.h"
25 #include "bytestream.h"
26 #include "internal.h"
27 
28 #define ALIAS_HEADER_SIZE 10
29 
31  const AVFrame *frame, int *got_packet)
32 {
33  int width, height, bits_pixel, i, j, length, ret;
34  uint8_t *in_buf, *buf;
35 
36 #if FF_API_CODED_FRAME
39  avctx->coded_frame->key_frame = 1;
41 #endif
42 
43  width = avctx->width;
44  height = avctx->height;
45 
46  if (width > 65535 || height > 65535 ||
47  width * height >= INT_MAX / 4 - ALIAS_HEADER_SIZE) {
48  av_log(avctx, AV_LOG_ERROR, "Invalid image size %dx%d.\n", width, height);
49  return AVERROR_INVALIDDATA;
50  }
51 
52  switch (avctx->pix_fmt) {
53  case AV_PIX_FMT_GRAY8:
54  bits_pixel = 8;
55  break;
56  case AV_PIX_FMT_BGR24:
57  bits_pixel = 24;
58  break;
59  default:
60  return AVERROR(EINVAL);
61  }
62 
63  length = ALIAS_HEADER_SIZE + 4 * width * height; // max possible
64  if ((ret = ff_alloc_packet2(avctx, pkt, length, ALIAS_HEADER_SIZE + height*2)) < 0) {
65  av_log(avctx, AV_LOG_ERROR, "Error getting output packet of size %d.\n", length);
66  return ret;
67  }
68 
69  buf = pkt->data;
70 
71  /* Encode header. */
72  bytestream_put_be16(&buf, width);
73  bytestream_put_be16(&buf, height);
74  bytestream_put_be32(&buf, 0); /* X, Y offset */
75  bytestream_put_be16(&buf, bits_pixel);
76 
77  for (j = 0; j < height; j++) {
78  in_buf = frame->data[0] + frame->linesize[0] * j;
79  for (i = 0; i < width; ) {
80  int count = 0;
81  int pixel;
82 
83  if (avctx->pix_fmt == AV_PIX_FMT_GRAY8) {
84  pixel = *in_buf;
85  while (count < 255 && count + i < width && pixel == *in_buf) {
86  count++;
87  in_buf++;
88  }
89  bytestream_put_byte(&buf, count);
90  bytestream_put_byte(&buf, pixel);
91  } else { /* AV_PIX_FMT_BGR24 */
92  pixel = AV_RB24(in_buf);
93  while (count < 255 && count + i < width &&
94  pixel == AV_RB24(in_buf)) {
95  count++;
96  in_buf += 3;
97  }
98  bytestream_put_byte(&buf, count);
99  bytestream_put_be24(&buf, pixel);
100  }
101  i += count;
102  }
103  }
104 
105  /* Total length */
106  av_shrink_packet(pkt, buf - pkt->data);
107  pkt->flags |= AV_PKT_FLAG_KEY;
108  *got_packet = 1;
109 
110  return 0;
111 }
112 
114  .name = "alias_pix",
115  .long_name = NULL_IF_CONFIG_SMALL("Alias/Wavefront PIX image"),
116  .type = AVMEDIA_TYPE_VIDEO,
117  .id = AV_CODEC_ID_ALIAS_PIX,
118  .encode2 = encode_frame,
119  .pix_fmts = (const enum AVPixelFormat[]) {
121  },
122 };
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
This structure describes decoded (raw) audio or video data.
Definition: frame.h:295
void av_shrink_packet(AVPacket *pkt, int size)
Reduce packet size, correctly zeroing padding.
Definition: avpacket.c:101
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1778
static AVPacket pkt
AVCodec.
Definition: avcodec.h:3484
int ff_alloc_packet2(AVCodecContext *avctx, AVPacket *avpkt, int64_t size, int64_t min_size)
Check AVPacket size and/or allocate data.
Definition: encode.c:32
uint8_t
#define height
uint8_t * data
Definition: avcodec.h:1480
#define av_log(a,...)
#define AV_PKT_FLAG_KEY
The packet contains a keyframe.
Definition: avcodec.h:1512
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:259
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
#define ALIAS_HEADER_SIZE
Definition: aliaspixenc.c:28
GLsizei GLsizei * length
Definition: opengl_enc.c:114
const char * name
Name of the codec implementation.
Definition: avcodec.h:3491
GLsizei count
Definition: opengl_enc.c:108
int flags
A combination of AV_PKT_FLAG values.
Definition: avcodec.h:1486
enum AVPictureType pict_type
Picture type of the frame.
Definition: frame.h:378
#define width
int width
picture width / height.
Definition: avcodec.h:1741
these buffered frames must be flushed immediately if a new input produces new the filter must not call request_frame to get more It must just process the frame or queue it The task of requesting more frames is left to the filter s request_frame method or the application If a filter has several the filter must be ready for frames arriving randomly on any input any filter with several inputs will most likely require some kind of queuing mechanism It is perfectly acceptable to have a limited queue and to drop frames when the inputs are too unbalanced request_frame For filters that do not use the this method is called when a frame is wanted on an output For a it should directly call filter_frame on the corresponding output For a if there are queued frames already one of these frames should be pushed If the filter should request a frame on one of its repeatedly until at least one frame has been pushed Return or at least make progress towards producing a frame
packed RGB 8:8:8, 24bpp, BGRBGR...
Definition: pixfmt.h:69
AVCodec ff_alias_pix_encoder
Definition: aliaspixenc.c:113
Libavcodec external API header.
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_WL16 uint64_t_TMPL AV_WB64 unsigned int_TMPL AV_WB32 unsigned int_TMPL AV_RB24
Definition: bytestream.h:87
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:326
main external API structure.
Definition: avcodec.h:1568
void * buf
Definition: avisynth_c.h:766
uint8_t pixel
Definition: tiny_ssim.c:42
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:309
Y , 8bpp.
Definition: pixfmt.h:74
#define FF_DISABLE_DEPRECATION_WARNINGS
Definition: internal.h:84
common internal api header.
attribute_deprecated AVFrame * coded_frame
the picture in the bitstream
Definition: avcodec.h:2818
#define FF_ENABLE_DEPRECATION_WARNINGS
Definition: internal.h:85
int key_frame
1 -> keyframe, 0-> not
Definition: frame.h:373
static int encode_frame(AVCodecContext *avctx, AVPacket *pkt, const AVFrame *frame, int *got_packet)
Definition: aliaspixenc.c:30
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later.That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another.Frame references ownership and permissions
AVPixelFormat
Pixel format.
Definition: pixfmt.h:64
This structure stores compressed data.
Definition: avcodec.h:1457