From acfd8f0fdb54b6d14e1584138fffd21edeaf4a2f Mon Sep 17 00:00:00 2001 From: Mike Melanson Date: Wed, 17 Nov 2004 03:45:53 +0000 Subject: native QPEG video decoder, courtesy of Konstantin Shishkov Originally committed as revision 3688 to svn://svn.ffmpeg.org/ffmpeg/trunk --- libavcodec/qpeg.c | 303 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 303 insertions(+) create mode 100644 libavcodec/qpeg.c (limited to 'libavcodec/qpeg.c') diff --git a/libavcodec/qpeg.c b/libavcodec/qpeg.c new file mode 100644 index 0000000000..bb6467b331 --- /dev/null +++ b/libavcodec/qpeg.c @@ -0,0 +1,303 @@ +/* + * QPEG codec + * Copyright (c) 2004 Konstantin Shishkov + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2 of the License, or (at your option) any later version. + * + * This library is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this library; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + * + */ + +/** + * @file qpeg.c + * QPEG codec. + */ + +#include "avcodec.h" +#include "mpegvideo.h" + +typedef struct QpegContext{ + AVCodecContext *avctx; + AVFrame pic; + uint8_t *refdata; +} QpegContext; + +static void qpeg_decode_intra(uint8_t *src, uint8_t *dst, int size, + int stride, int width, int height) +{ + int i; + int code; + int c0, c1; + int run, copy; + int filled = 0; + + height--; + dst = dst + height * stride; + + while(size > 0) { + code = *src++; + size--; + run = copy = 0; + if(code == 0xFC) /* end-of-picture code */ + break; + if(code >= 0xF8) { /* very long run */ + c0 = *src++; + c1 = *src++; + size -= 2; + run = ((code & 0x7) << 16) + (c0 << 8) + c1 + 2; + } else if (code >= 0xF0) { /* long run */ + c0 = *src++; + size--; + run = ((code & 0xF) << 8) + c0 + 2; + } else if (code >= 0xE0) { /* short run */ + run = (code & 0x1F) + 2; + } else if (code >= 0xC0) { /* very long copy */ + c0 = *src++; + c1 = *src++; + size -= 2; + copy = ((code & 0x3F) << 16) + (c0 << 8) + c1 + 1; + } else if (code >= 0x80) { /* long copy */ + c0 = *src++; + size--; + copy = ((code & 0x7F) << 8) + c0 + 1; + } else { /* short copy */ + copy = code + 1; + } + + /* perform actual run or copy */ + if(run) { + int p; + + p = *src++; + size--; + for(i = 0; i < run; i++) { + dst[filled++] = p; + if (filled >= width) { + filled = 0; + dst -= stride; + } + } + } else { + for(i = 0; i < copy; i++) { + dst[filled++] = *src++; + if (filled >= width) { + filled = 0; + dst -= stride; + } + } + size -= copy; + } + } +} + +static int qpeg_table_h[16] = + { 0x00, 0x20, 0x20, 0x20, 0x18, 0x10, 0x10, 0x20, 0x10, 0x08, 0x18, 0x08, 0x08, 0x18, 0x10, 0x04}; +static int qpeg_table_w[16] = + { 0x00, 0x20, 0x18, 0x08, 0x18, 0x10, 0x20, 0x10, 0x08, 0x10, 0x20, 0x20, 0x08, 0x10, 0x18, 0x04}; + +/* Decodes delta frames */ +static void qpeg_decode_inter(uint8_t *src, uint8_t *dst, int size, + int stride, int width, int height, + int delta, uint8_t *ctable, uint8_t *refdata) +{ + int i, j; + int code; + int filled = 0; + uint8_t *blkdata; + + /* copy prev frame */ + for(i = 0; i < height; i++) + memcpy(refdata + (i * width), dst + (i * stride), width); + + blkdata = src - 0x86; + height--; + dst = dst + height * stride; + + while(size > 0) { + code = *src++; + size--; + + if(delta) { + /* motion compensation */ + while((code & 0xF0) == 0xF0) { + if(delta == 1) { + int me_idx; + int me_w, me_h, me_x, me_y; + uint8_t *me_plane; + int corr, val; + + /* get block size by index */ + me_idx = code & 0xF; + me_w = qpeg_table_w[me_idx]; + me_h = qpeg_table_h[me_idx]; + + /* extract motion vector */ + corr = *src++; + size--; + + val = corr >> 4; + if(val > 7) + val -= 16; + me_x = val; + + val = corr & 0xF; + if(val > 7) + val -= 16; + me_y = val; + + /* do motion compensation */ + me_plane = refdata + (filled + me_x) + (height - me_y) * width; + for(j = 0; j < me_h; j++) { + for(i = 0; i < me_w; i++) + dst[filled + i - (j * stride)] = me_plane[i - (j * width)]; + } + } + code = *src++; + size--; + } + } + + if(code == 0xE0) /* end-of-picture code */ + break; + if(code > 0xE0) { /* run code: 0xE1..0xFF */ + int p; + + code &= 0x1F; + p = *src++; + size--; + for(i = 0; i <= code; i++) { + dst[filled++] = p; + if(filled >= width) { + filled = 0; + dst -= stride; + height--; + } + } + } else if(code >= 0xC0) { /* copy code: 0xC0..0xDF */ + code &= 0x1F; + + for(i = 0; i <= code; i++) { + dst[filled++] = *src++; + if(filled >= width) { + filled = 0; + dst -= stride; + height--; + } + } + size -= code + 1; + } else if(code >= 0x80) { /* skip code: 0x80..0xBF */ + int skip; + + code &= 0x3F; + /* codes 0x80 and 0x81 are actually escape codes, + skip value minus constant is in the next byte */ + if(!code) + skip = (*src++) + 64; + else if(code == 1) + skip = (*src++) + 320; + else + skip = code; + filled += skip; + while( filled >= width) { + filled -= width; + dst -= stride; + height--; + } + } else { + /* zero code treated as one-pixel skip */ + if(code) + dst[filled++] = ctable[code & 0x7F]; + else + filled++; + if(filled >= width) { + filled = 0; + dst -= stride; + height--; + } + } + } +} + +static int decode_frame(AVCodecContext *avctx, + void *data, int *data_size, + uint8_t *buf, int buf_size) +{ + QpegContext * const a = avctx->priv_data; + AVFrame * const p= (AVFrame*)&a->pic; + uint8_t* outdata; + int delta; + + /* special case for last picture */ + if (buf_size == 0) { + return 0; + } + + if(p->data[0]) + avctx->release_buffer(avctx, p); + + p->reference= 0; + if(avctx->get_buffer(avctx, p) < 0){ + av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n"); + return -1; + } + outdata = a->pic.data[0]; + if(buf[0x85] == 0x10) { + qpeg_decode_intra(buf+0x86, outdata, buf_size - 0x86, a->pic.linesize[0], avctx->width, avctx->height); + } else { + delta = buf[0x85]; + qpeg_decode_inter(buf+0x86, outdata, buf_size - 0x86, a->pic.linesize[0], avctx->width, avctx->height, delta, buf + 4, a->refdata); + } + + /* make the palette available on the way out */ + memcpy(a->pic.data[1], a->avctx->palctrl->palette, AVPALETTE_SIZE); + if (a->avctx->palctrl->palette_changed) { + a->pic.palette_has_changed = 1; + a->avctx->palctrl->palette_changed = 0; + } + + *data_size = sizeof(AVFrame); + *(AVFrame*)data = a->pic; + + return buf_size; +} + +static int decode_init(AVCodecContext *avctx){ + QpegContext * const a = avctx->priv_data; + + a->avctx = avctx; + avctx->pix_fmt= PIX_FMT_PAL8; + avctx->has_b_frames = 0; + a->pic.data[0] = NULL; + a->refdata = av_malloc(avctx->width * avctx->height); + + return 0; +} + +static int decode_end(AVCodecContext *avctx){ + QpegContext * const a = avctx->priv_data; + + av_free(a->refdata); + return 0; +} + +AVCodec qpeg_decoder = { + "qpeg", + CODEC_TYPE_VIDEO, + CODEC_ID_QPEG, + sizeof(QpegContext), + decode_init, + NULL, + decode_end, + decode_frame, + CODEC_CAP_DR1, +}; -- cgit v1.2.3