FFmpeg
xl.c
Go to the documentation of this file.
1 /*
2  * Miro VideoXL codec
3  * Copyright (c) 2004 Konstantin Shishkov
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 /**
23  * @file
24  * Miro VideoXL codec.
25  */
26 
27 #include "libavutil/common.h"
28 #include "libavutil/intreadwrite.h"
29 #include "avcodec.h"
30 #include "internal.h"
31 
32 static const int xl_table[32] = {
33  0, 1, 2, 3, 4, 5, 6, 7,
34  8, 9, 12, 15, 20, 25, 34, 46,
35  64, 82, 94, 103, 108, 113, 116, 119,
36  120, 121, 122, 123, 124, 125, 126, 127
37 };
38 
39 static int decode_frame(AVCodecContext *avctx,
40  void *data, int *got_frame,
41  AVPacket *avpkt)
42 {
43  const uint8_t *buf = avpkt->data;
44  int buf_size = avpkt->size;
45  AVFrame *const p = data;
46  uint8_t *Y, *U, *V;
47  int i, j, ret;
48  int stride;
49  uint32_t val;
50  int y0, y1, y2, y3 = 0, c0 = 0, c1 = 0;
51 
52  if (avctx->width % 4) {
53  av_log(avctx, AV_LOG_ERROR, "width is not a multiple of 4\n");
54  return AVERROR_INVALIDDATA;
55  }
56  if (buf_size < avctx->width * avctx->height) {
57  av_log(avctx, AV_LOG_ERROR, "Packet is too small\n");
58  return AVERROR_INVALIDDATA;
59  }
60 
61  if ((ret = ff_get_buffer(avctx, p, 0)) < 0)
62  return ret;
64  p->key_frame = 1;
65 
66  Y = p->data[0];
67  U = p->data[1];
68  V = p->data[2];
69 
70  stride = avctx->width - 4;
71 
72  for (i = 0; i < avctx->height; i++) {
73  /* lines are stored in reversed order */
74  buf += stride;
75 
76  for (j = 0; j < avctx->width; j += 4) {
77  /* value is stored in LE dword with word swapped */
78  val = AV_RL32(buf);
79  buf -= 4;
80  val = ((val >> 16) & 0xFFFF) | ((val & 0xFFFF) << 16);
81 
82  if (!j)
83  y0 = (val & 0x1F) << 2;
84  else
85  y0 = y3 + xl_table[val & 0x1F];
86  val >>= 5;
87  y1 = y0 + xl_table[val & 0x1F];
88  val >>= 5;
89  y2 = y1 + xl_table[val & 0x1F];
90  val >>= 6; /* align to word */
91  y3 = y2 + xl_table[val & 0x1F];
92  val >>= 5;
93  if (!j)
94  c0 = (val & 0x1F) << 2;
95  else
96  c0 += xl_table[val & 0x1F];
97  val >>= 5;
98  if (!j)
99  c1 = (val & 0x1F) << 2;
100  else
101  c1 += xl_table[val & 0x1F];
102 
103  Y[j + 0] = y0 << 1;
104  Y[j + 1] = y1 << 1;
105  Y[j + 2] = y2 << 1;
106  Y[j + 3] = y3 << 1;
107 
108  U[j >> 2] = c0 << 1;
109  V[j >> 2] = c1 << 1;
110  }
111 
112  buf += avctx->width + 4;
113  Y += p->linesize[0];
114  U += p->linesize[1];
115  V += p->linesize[2];
116  }
117 
118  *got_frame = 1;
119 
120  return buf_size;
121 }
122 
124 {
125  avctx->pix_fmt = AV_PIX_FMT_YUV411P;
126 
127  return 0;
128 }
129 
131  .name = "xl",
132  .long_name = NULL_IF_CONFIG_SMALL("Miro VideoXL"),
133  .type = AVMEDIA_TYPE_VIDEO,
134  .id = AV_CODEC_ID_VIXL,
135  .init = decode_init,
136  .decode = decode_frame,
137  .capabilities = AV_CODEC_CAP_DR1,
138 };
const char const char void * val
Definition: avisynth_c.h:863
#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
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:100
int size
Definition: avcodec.h:1481
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1778
AVCodec.
Definition: avcodec.h:3492
static const int xl_table[32]
Definition: xl.c:32
uint8_t
#define av_cold
Definition: attributes.h:82
uint8_t * data
Definition: avcodec.h:1480
static const uint64_t c1
Definition: murmur3.c:49
#define av_log(a,...)
#define U(x)
Definition: vp56_arith.h:37
#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
const char * name
Name of the codec implementation.
Definition: avcodec.h:3499
enum AVPictureType pict_type
Picture type of the frame.
Definition: frame.h:378
#define Y
Definition: boxblur.h:38
static av_cold int decode_init(AVCodecContext *avctx)
Definition: xl.c:123
#define width
int width
picture width / height.
Definition: avcodec.h:1741
Libavcodec external API header.
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
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: decode.c:1968
void * buf
Definition: avisynth_c.h:766
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:309
static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: xl.c:39
common internal api header.
common internal and external API header
planar YUV 4:1:1, 12bpp, (1 Cr & Cb sample per 4x1 Y samples)
Definition: pixfmt.h:73
int key_frame
1 -> keyframe, 0-> not
Definition: frame.h:373
AVCodec ff_xl_decoder
Definition: xl.c:130
#define stride
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_RL32
Definition: bytestream.h:87
This structure stores compressed data.
Definition: avcodec.h:1457
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: avcodec.h:984
#define V
Definition: avdct.c:30