FFmpeg
8bps.c
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1 /*
2  * Quicktime Planar RGB (8BPS) Video Decoder
3  * Copyright (C) 2003 Roberto Togni
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  * QT 8BPS Video Decoder by Roberto Togni
25  * For more information about the 8BPS format, visit:
26  * http://www.pcisys.net/~melanson/codecs/
27  *
28  * Supports: PAL8 (RGB 8bpp, paletted)
29  * : GBRP (RGB 24bpp)
30  * : GBRAP (RGB 32bpp, 4th plane is alpha)
31  */
32 
33 #include <string.h>
34 
35 #include "libavutil/intreadwrite.h"
36 #include "libavutil/internal.h"
37 #include "avcodec.h"
38 #include "codec_internal.h"
39 #include "decode.h"
40 
41 typedef struct EightBpsContext {
43 
44  uint8_t planes;
45  uint8_t planemap[4];
46 
47  uint32_t pal[256];
49 
51  int *got_frame, AVPacket *avpkt)
52 {
53  const uint8_t *buf = avpkt->data;
54  int buf_size = avpkt->size;
55  EightBpsContext * const c = avctx->priv_data;
56  const uint8_t *encoded = buf;
57  uint8_t *pixptr, *pixptr_end;
58  unsigned int height = avctx->height; // Real image height
59  unsigned int dlen, p, row;
60  const uint8_t *lp, *dp, *ep;
61  uint8_t count;
62  const uint8_t *planemap = c->planemap;
63  unsigned int planes = c->planes;
64  int ret;
65 
66  if (buf_size < planes * height * (2 + 2*((avctx->width+128)/129)))
67  return AVERROR_INVALIDDATA;
68 
69  if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
70  return ret;
71 
72  ep = encoded + buf_size;
73 
74  /* Set data pointer after line lengths */
75  dp = encoded + planes * (height << 1);
76 
77  for (p = 0; p < planes; p++) {
78  const int pi = planemap[p];
79  /* Lines length pointer for this plane */
80  lp = encoded + p * (height << 1);
81 
82  /* Decode a plane */
83  for (row = 0; row < height; row++) {
84  pixptr = frame->data[pi] + row * frame->linesize[pi];
85  pixptr_end = pixptr + frame->linesize[pi];
86  if (ep - lp < row * 2 + 2)
87  return AVERROR_INVALIDDATA;
88  dlen = AV_RB16(lp + row * 2);
89  /* Decode a row of this plane */
90  while (dlen > 0) {
91  if (ep - dp <= 1)
92  return AVERROR_INVALIDDATA;
93  if ((count = *dp++) <= 127) {
94  count++;
95  dlen -= count + 1;
96  if (pixptr_end - pixptr < count)
97  break;
98  if (ep - dp < count)
99  return AVERROR_INVALIDDATA;
100  memcpy(pixptr, dp, count);
101  pixptr += count;
102  dp += count;
103  } else {
104  count = 257 - count;
105  if (pixptr_end - pixptr < count)
106  break;
107  memset(pixptr, dp[0], count);
108  pixptr += count;
109  dp++;
110  dlen -= 2;
111  }
112  }
113  }
114  }
115 
116  if (avctx->bits_per_coded_sample <= 8) {
117 #if FF_API_PALETTE_HAS_CHANGED
119  frame->palette_has_changed =
120 #endif
121  ff_copy_palette(c->pal, avpkt, avctx);
122 #if FF_API_PALETTE_HAS_CHANGED
124 #endif
125 
126  memcpy(frame->data[1], c->pal, AVPALETTE_SIZE);
127  }
128 
129  *got_frame = 1;
130 
131  /* always report that the buffer was completely consumed */
132  return buf_size;
133 }
134 
136 {
137  EightBpsContext * const c = avctx->priv_data;
138 
139  c->avctx = avctx;
140 
141  switch (avctx->bits_per_coded_sample) {
142  case 8:
143  avctx->pix_fmt = AV_PIX_FMT_PAL8;
144  c->planes = 1;
145  c->planemap[0] = 0; // 1st plane is palette indexes
146  break;
147  case 24:
148  avctx->pix_fmt = AV_PIX_FMT_GBRP;
149  c->planes = 3;
150  c->planemap[0] = 2; // 1st plane is red
151  c->planemap[1] = 0; // 2nd plane is green
152  c->planemap[2] = 1; // 3rd plane is blue
153  break;
154  case 32:
155  avctx->pix_fmt = AV_PIX_FMT_GBRAP;
156  c->planes = 4;
157  break;
158  default:
159  av_log(avctx, AV_LOG_ERROR, "Error: Unsupported color depth: %u.\n",
160  avctx->bits_per_coded_sample);
161  return AVERROR_INVALIDDATA;
162  }
163 
164  if (avctx->pix_fmt == AV_PIX_FMT_GBRAP) {
165  c->planemap[0] = 2; // 1st plane is red
166  c->planemap[1] = 0; // 2nd plane is green
167  c->planemap[2] = 1; // 3rd plane is blue
168  c->planemap[3] = 3; // 4th plane is alpha
169  }
170  return 0;
171 }
172 
174  .p.name = "8bps",
175  CODEC_LONG_NAME("QuickTime 8BPS video"),
176  .p.type = AVMEDIA_TYPE_VIDEO,
177  .p.id = AV_CODEC_ID_8BPS,
178  .priv_data_size = sizeof(EightBpsContext),
179  .init = decode_init,
181  .p.capabilities = AV_CODEC_CAP_DR1,
182 };
FF_ENABLE_DEPRECATION_WARNINGS
#define FF_ENABLE_DEPRECATION_WARNINGS
Definition: internal.h:73
decode_init
static av_cold int decode_init(AVCodecContext *avctx)
Definition: 8bps.c:135
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:374
AVPacket::data
uint8_t * data
Definition: packet.h:524
FFCodec
Definition: codec_internal.h:126
FFCodec::p
AVCodec p
The public AVCodec.
Definition: codec_internal.h:130
AV_PIX_FMT_GBRAP
@ AV_PIX_FMT_GBRAP
planar GBRA 4:4:4:4 32bpp
Definition: pixfmt.h:212
EightBpsContext::pal
uint32_t pal[256]
Definition: 8bps.c:47
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:180
av_cold
#define av_cold
Definition: attributes.h:90
ff_eightbps_decoder
const FFCodec ff_eightbps_decoder
Definition: 8bps.c:173
FF_CODEC_DECODE_CB
#define FF_CODEC_DECODE_CB(func)
Definition: codec_internal.h:286
intreadwrite.h
decode.h
EightBpsContext::avctx
AVCodecContext * avctx
Definition: 8bps.c:42
CODEC_LONG_NAME
#define CODEC_LONG_NAME(str)
Definition: codec_internal.h:271
AVPALETTE_SIZE
#define AVPALETTE_SIZE
Definition: pixfmt.h:32
c
Undefined Behavior In the C some operations are like signed integer dereferencing freed accessing outside allocated Undefined Behavior must not occur in a C it is not safe even if the output of undefined operations is unused The unsafety may seem nit picking but Optimizing compilers have in fact optimized code on the assumption that no undefined Behavior occurs Optimizing code based on wrong assumptions can and has in some cases lead to effects beyond the output of computations The signed integer overflow problem in speed critical code Code which is highly optimized and works with signed integers sometimes has the problem that often the output of the computation does not c
Definition: undefined.txt:32
ff_get_buffer
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: decode.c:1556
init
int(* init)(AVBSFContext *ctx)
Definition: dts2pts.c:366
AV_CODEC_CAP_DR1
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() or get_encode_buffer() for allocating buffers and supports custom allocators.
Definition: codec.h:52
AVPacket::size
int size
Definition: packet.h:525
codec_internal.h
AV_CODEC_ID_8BPS
@ AV_CODEC_ID_8BPS
Definition: codec_id.h:100
height
#define height
AVCodecContext::bits_per_coded_sample
int bits_per_coded_sample
bits per sample/pixel from the demuxer (needed for huffyuv).
Definition: avcodec.h:1567
EightBpsContext::planes
uint8_t planes
Definition: 8bps.c:44
EightBpsContext::planemap
uint8_t planemap[4]
Definition: 8bps.c:45
EightBpsContext
Definition: 8bps.c:41
internal.h
AVCodec::name
const char * name
Name of the codec implementation.
Definition: codec.h:194
AVCodecContext::height
int height
Definition: avcodec.h:618
AVCodecContext::pix_fmt
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:657
avcodec.h
AV_PIX_FMT_PAL8
@ AV_PIX_FMT_PAL8
8 bits with AV_PIX_FMT_RGB32 palette
Definition: pixfmt.h:84
ret
ret
Definition: filter_design.txt:187
frame
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
Definition: filter_design.txt:264
AVCodecContext
main external API structure.
Definition: avcodec.h:445
planes
static const struct @400 planes[]
FF_DISABLE_DEPRECATION_WARNINGS
#define FF_DISABLE_DEPRECATION_WARNINGS
Definition: internal.h:72
AV_PIX_FMT_GBRP
@ AV_PIX_FMT_GBRP
planar GBR 4:4:4 24bpp
Definition: pixfmt.h:165
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
decode_frame
static int decode_frame(AVCodecContext *avctx, AVFrame *frame, int *got_frame, AVPacket *avpkt)
Definition: 8bps.c:50
AVCodecContext::priv_data
void * priv_data
Definition: avcodec.h:472
AVPacket
This structure stores compressed data.
Definition: packet.h:501
AVCodecContext::width
int width
picture width / height.
Definition: avcodec.h:618
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:27
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:61
ff_copy_palette
int ff_copy_palette(void *dst, const AVPacket *src, void *logctx)
Check whether the side-data of src contains a palette of size AVPALETTE_SIZE; if so,...
Definition: decode.c:2070
AV_RB16
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_WB24 unsigned int_TMPL AV_RB16
Definition: bytestream.h:98