/libavcodec/8bps.c

http://github.com/FFmpeg/FFmpeg · C · 193 lines · 133 code · 24 blank · 36 comment · 23 complexity · add12327ea3d08356ef8533d688745f5 MD5 · raw file

  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. * @file
  23. * QT 8BPS Video Decoder by Roberto Togni
  24. * For more information about the 8BPS format, visit:
  25. * http://www.pcisys.net/~melanson/codecs/
  26. *
  27. * Supports: PAL8 (RGB 8bpp, paletted)
  28. * : BGR24 (RGB 24bpp) (can also output it as RGB32)
  29. * : RGB32 (RGB 32bpp, 4th plane is alpha)
  30. */
  31. #include <stdio.h>
  32. #include <stdlib.h>
  33. #include <string.h>
  34. #include "libavutil/internal.h"
  35. #include "libavutil/intreadwrite.h"
  36. #include "avcodec.h"
  37. #include "internal.h"
  38. static const enum AVPixelFormat pixfmt_rgb24[] = {
  39. AV_PIX_FMT_BGR24, AV_PIX_FMT_0RGB32, AV_PIX_FMT_NONE };
  40. typedef struct EightBpsContext {
  41. AVCodecContext *avctx;
  42. unsigned char planes;
  43. unsigned char planemap[4];
  44. uint32_t pal[256];
  45. } EightBpsContext;
  46. static int decode_frame(AVCodecContext *avctx, void *data,
  47. int *got_frame, AVPacket *avpkt)
  48. {
  49. AVFrame *frame = data;
  50. const uint8_t *buf = avpkt->data;
  51. int buf_size = avpkt->size;
  52. EightBpsContext * const c = avctx->priv_data;
  53. const unsigned char *encoded = buf;
  54. unsigned char *pixptr, *pixptr_end;
  55. unsigned int height = avctx->height; // Real image height
  56. unsigned int dlen, p, row;
  57. const unsigned char *lp, *dp, *ep;
  58. unsigned char count;
  59. unsigned int px_inc;
  60. unsigned int planes = c->planes;
  61. unsigned char *planemap = c->planemap;
  62. int ret;
  63. if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
  64. return ret;
  65. ep = encoded + buf_size;
  66. /* Set data pointer after line lengths */
  67. dp = encoded + planes * (height << 1);
  68. px_inc = planes + (avctx->pix_fmt == AV_PIX_FMT_0RGB32);
  69. for (p = 0; p < planes; p++) {
  70. /* Lines length pointer for this plane */
  71. lp = encoded + p * (height << 1);
  72. /* Decode a plane */
  73. for (row = 0; row < height; row++) {
  74. pixptr = frame->data[0] + row * frame->linesize[0] + planemap[p];
  75. pixptr_end = pixptr + frame->linesize[0];
  76. if (ep - lp < row * 2 + 2)
  77. return AVERROR_INVALIDDATA;
  78. dlen = av_be2ne16(*(const unsigned short *)(lp + row * 2));
  79. /* Decode a row of this plane */
  80. while (dlen > 0) {
  81. if (ep - dp <= 1)
  82. return AVERROR_INVALIDDATA;
  83. if ((count = *dp++) <= 127) {
  84. count++;
  85. dlen -= count + 1;
  86. if (pixptr_end - pixptr < count * px_inc)
  87. break;
  88. if (ep - dp < count)
  89. return AVERROR_INVALIDDATA;
  90. while (count--) {
  91. *pixptr = *dp++;
  92. pixptr += px_inc;
  93. }
  94. } else {
  95. count = 257 - count;
  96. if (pixptr_end - pixptr < count * px_inc)
  97. break;
  98. while (count--) {
  99. *pixptr = *dp;
  100. pixptr += px_inc;
  101. }
  102. dp++;
  103. dlen -= 2;
  104. }
  105. }
  106. }
  107. }
  108. if (avctx->bits_per_coded_sample <= 8) {
  109. int size;
  110. const uint8_t *pal = av_packet_get_side_data(avpkt,
  111. AV_PKT_DATA_PALETTE,
  112. &size);
  113. if (pal && size == AVPALETTE_SIZE) {
  114. frame->palette_has_changed = 1;
  115. memcpy(c->pal, pal, AVPALETTE_SIZE);
  116. } else if (pal) {
  117. av_log(avctx, AV_LOG_ERROR, "Palette size %d is wrong\n", size);
  118. }
  119. memcpy (frame->data[1], c->pal, AVPALETTE_SIZE);
  120. }
  121. *got_frame = 1;
  122. /* always report that the buffer was completely consumed */
  123. return buf_size;
  124. }
  125. static av_cold int decode_init(AVCodecContext *avctx)
  126. {
  127. EightBpsContext * const c = avctx->priv_data;
  128. c->avctx = avctx;
  129. switch (avctx->bits_per_coded_sample) {
  130. case 8:
  131. avctx->pix_fmt = AV_PIX_FMT_PAL8;
  132. c->planes = 1;
  133. c->planemap[0] = 0; // 1st plane is palette indexes
  134. break;
  135. case 24:
  136. avctx->pix_fmt = ff_get_format(avctx, pixfmt_rgb24);
  137. c->planes = 3;
  138. c->planemap[0] = 2; // 1st plane is red
  139. c->planemap[1] = 1; // 2nd plane is green
  140. c->planemap[2] = 0; // 3rd plane is blue
  141. break;
  142. case 32:
  143. avctx->pix_fmt = AV_PIX_FMT_RGB32;
  144. c->planes = 4;
  145. /* handle planemap setup later for decoding rgb24 data as rbg32 */
  146. break;
  147. default:
  148. av_log(avctx, AV_LOG_ERROR, "Error: Unsupported color depth: %u.\n",
  149. avctx->bits_per_coded_sample);
  150. return AVERROR_INVALIDDATA;
  151. }
  152. if (avctx->pix_fmt == AV_PIX_FMT_RGB32) {
  153. c->planemap[0] = HAVE_BIGENDIAN ? 1 : 2; // 1st plane is red
  154. c->planemap[1] = HAVE_BIGENDIAN ? 2 : 1; // 2nd plane is green
  155. c->planemap[2] = HAVE_BIGENDIAN ? 3 : 0; // 3rd plane is blue
  156. c->planemap[3] = HAVE_BIGENDIAN ? 0 : 3; // 4th plane is alpha
  157. }
  158. return 0;
  159. }
  160. AVCodec ff_eightbps_decoder = {
  161. .name = "8bps",
  162. .long_name = NULL_IF_CONFIG_SMALL("QuickTime 8BPS video"),
  163. .type = AVMEDIA_TYPE_VIDEO,
  164. .id = AV_CODEC_ID_8BPS,
  165. .priv_data_size = sizeof(EightBpsContext),
  166. .init = decode_init,
  167. .decode = decode_frame,
  168. .capabilities = AV_CODEC_CAP_DR1,
  169. };