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  * : BGR24 (RGB 24bpp) (can also output it as RGB32)
30  * : RGB32 (RGB 32bpp, 4th plane is alpha)
31  */
32 
33 #include <stdio.h>
34 #include <stdlib.h>
35 #include <string.h>
36 
37 #include "libavutil/internal.h"
38 #include "libavutil/intreadwrite.h"
39 #include "avcodec.h"
40 #include "internal.h"
41 
42 
43 static const enum AVPixelFormat pixfmt_rgb24[] = {
45 
46 typedef struct EightBpsContext {
48 
49  unsigned char planes;
50  unsigned char planemap[4];
51 
52  uint32_t pal[256];
54 
56  int *got_frame, AVPacket *avpkt)
57 {
58  AVFrame *frame = data;
59  const uint8_t *buf = avpkt->data;
60  int buf_size = avpkt->size;
61  EightBpsContext * const c = avctx->priv_data;
62  const unsigned char *encoded = buf;
63  unsigned char *pixptr, *pixptr_end;
64  unsigned int height = avctx->height; // Real image height
65  unsigned int dlen, p, row;
66  const unsigned char *lp, *dp, *ep;
67  unsigned char count;
68  unsigned int px_inc;
69  unsigned int planes = c->planes;
70  unsigned char *planemap = c->planemap;
71  int ret;
72 
73  if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
74  return ret;
75 
76  ep = encoded + buf_size;
77 
78  /* Set data pointer after line lengths */
79  dp = encoded + planes * (height << 1);
80 
81  px_inc = planes + (avctx->pix_fmt == AV_PIX_FMT_0RGB32);
82 
83  for (p = 0; p < planes; p++) {
84  /* Lines length pointer for this plane */
85  lp = encoded + p * (height << 1);
86 
87  /* Decode a plane */
88  for (row = 0; row < height; row++) {
89  pixptr = frame->data[0] + row * frame->linesize[0] + planemap[p];
90  pixptr_end = pixptr + frame->linesize[0];
91  if (ep - lp < row * 2 + 2)
92  return AVERROR_INVALIDDATA;
93  dlen = av_be2ne16(*(const unsigned short *)(lp + row * 2));
94  /* Decode a row of this plane */
95  while (dlen > 0) {
96  if (ep - dp <= 1)
97  return AVERROR_INVALIDDATA;
98  if ((count = *dp++) <= 127) {
99  count++;
100  dlen -= count + 1;
101  if (pixptr_end - pixptr < count * px_inc)
102  break;
103  if (ep - dp < count)
104  return AVERROR_INVALIDDATA;
105  while (count--) {
106  *pixptr = *dp++;
107  pixptr += px_inc;
108  }
109  } else {
110  count = 257 - count;
111  if (pixptr_end - pixptr < count * px_inc)
112  break;
113  while (count--) {
114  *pixptr = *dp;
115  pixptr += px_inc;
116  }
117  dp++;
118  dlen -= 2;
119  }
120  }
121  }
122  }
123 
124  if (avctx->bits_per_coded_sample <= 8) {
125  int size;
126  const uint8_t *pal = av_packet_get_side_data(avpkt,
128  &size);
129  if (pal && size == AVPALETTE_SIZE) {
130  frame->palette_has_changed = 1;
131  memcpy(c->pal, pal, AVPALETTE_SIZE);
132  } else if (pal) {
133  av_log(avctx, AV_LOG_ERROR, "Palette size %d is wrong\n", size);
134  }
135 
136  memcpy (frame->data[1], c->pal, AVPALETTE_SIZE);
137  }
138 
139  *got_frame = 1;
140 
141  /* always report that the buffer was completely consumed */
142  return buf_size;
143 }
144 
146 {
147  EightBpsContext * const c = avctx->priv_data;
148 
149  c->avctx = avctx;
150 
151  switch (avctx->bits_per_coded_sample) {
152  case 8:
153  avctx->pix_fmt = AV_PIX_FMT_PAL8;
154  c->planes = 1;
155  c->planemap[0] = 0; // 1st plane is palette indexes
156  break;
157  case 24:
158  avctx->pix_fmt = ff_get_format(avctx, pixfmt_rgb24);
159  c->planes = 3;
160  c->planemap[0] = 2; // 1st plane is red
161  c->planemap[1] = 1; // 2nd plane is green
162  c->planemap[2] = 0; // 3rd plane is blue
163  break;
164  case 32:
165  avctx->pix_fmt = AV_PIX_FMT_RGB32;
166  c->planes = 4;
167  /* handle planemap setup later for decoding rgb24 data as rbg32 */
168  break;
169  default:
170  av_log(avctx, AV_LOG_ERROR, "Error: Unsupported color depth: %u.\n",
171  avctx->bits_per_coded_sample);
172  return AVERROR_INVALIDDATA;
173  }
174 
175  if (avctx->pix_fmt == AV_PIX_FMT_RGB32) {
176  c->planemap[0] = HAVE_BIGENDIAN ? 1 : 2; // 1st plane is red
177  c->planemap[1] = HAVE_BIGENDIAN ? 2 : 1; // 2nd plane is green
178  c->planemap[2] = HAVE_BIGENDIAN ? 3 : 0; // 3rd plane is blue
179  c->planemap[3] = HAVE_BIGENDIAN ? 0 : 3; // 4th plane is alpha
180  }
181  return 0;
182 }
183 
185  .name = "8bps",
186  .long_name = NULL_IF_CONFIG_SMALL("QuickTime 8BPS video"),
187  .type = AVMEDIA_TYPE_VIDEO,
188  .id = AV_CODEC_ID_8BPS,
189  .priv_data_size = sizeof(EightBpsContext),
190  .init = decode_init,
191  .decode = decode_frame,
192  .capabilities = AV_CODEC_CAP_DR1,
193 };
int ff_get_format(AVCodecContext *avctx, const enum AVPixelFormat *fmt)
Select the (possibly hardware accelerated) pixel format.
Definition: decode.c:1326
#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:268
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:101
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:35
int size
Definition: avcodec.h:1469
uint32_t pal[256]
Definition: 8bps.c:52
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1766
AVCodec.
Definition: avcodec.h:3468
static void decode(AVCodecContext *dec_ctx, AVPacket *pkt, AVFrame *frame, FILE *outfile)
Definition: decode_audio.c:42
AVCodec ff_eightbps_decoder
Definition: 8bps.c:184
uint8_t
#define av_cold
Definition: attributes.h:82
8 bits with AV_PIX_FMT_RGB32 palette
Definition: pixfmt.h:77
#define AVPALETTE_SIZE
Definition: pixfmt.h:32
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
#define height
uint8_t * data
Definition: avcodec.h:1468
ptrdiff_t size
Definition: opengl_enc.c:101
int bits_per_coded_sample
bits per sample/pixel from the demuxer (needed for huffyuv).
Definition: avcodec.h:2776
#define av_log(a,...)
AVCodecContext * avctx
Definition: 8bps.c:47
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
An AV_PKT_DATA_PALETTE side data packet contains exactly AVPALETTE_SIZE bytes worth of palette...
Definition: avcodec.h:1181
uint8_t * av_packet_get_side_data(const AVPacket *pkt, enum AVPacketSideDataType type, int *size)
Get side information from packet.
Definition: avpacket.c:350
#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:3475
GLsizei count
Definition: opengl_enc.c:109
common internal API header
unsigned char planes
Definition: 8bps.c:49
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
static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: 8bps.c:55
Libavcodec external API header.
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:299
main external API structure.
Definition: avcodec.h:1556
#define AV_PIX_FMT_RGB32
Definition: pixfmt.h:357
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: decode.c:1919
void * buf
Definition: avisynth_c.h:690
static av_cold int decode_init(AVCodecContext *avctx)
Definition: 8bps.c:145
int palette_has_changed
Tell user application that palette has changed from previous frame.
Definition: frame.h:425
static enum AVPixelFormat pixfmt_rgb24[]
Definition: 8bps.c:43
unsigned char planemap[4]
Definition: 8bps.c:50
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:282
common internal api header.
void * priv_data
Definition: avcodec.h:1583
#define av_be2ne16(x)
Definition: bswap.h:92
AVPixelFormat
Pixel format.
Definition: pixfmt.h:64
This structure stores compressed data.
Definition: avcodec.h:1445
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: avcodec.h:972
#define AV_PIX_FMT_0RGB32
Definition: pixfmt.h:361