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00022 #include "parser.h"
00023 #include "pnm.h"
00024
00025
00026 static int pnm_parse(AVCodecParserContext *s, AVCodecContext *avctx,
00027 const uint8_t **poutbuf, int *poutbuf_size,
00028 const uint8_t *buf, int buf_size)
00029 {
00030 ParseContext *pc = s->priv_data;
00031 PNMContext pnmctx;
00032 int next;
00033
00034 for (; pc->overread > 0; pc->overread--) {
00035 pc->buffer[pc->index++]= pc->buffer[pc->overread_index++];
00036 }
00037 retry:
00038 if (pc->index) {
00039 pnmctx.bytestream_start =
00040 pnmctx.bytestream = pc->buffer;
00041 pnmctx.bytestream_end = pc->buffer + pc->index;
00042 } else {
00043 pnmctx.bytestream_start =
00044 pnmctx.bytestream = (uint8_t *) buf;
00045 pnmctx.bytestream_end = (uint8_t *) buf + buf_size;
00046 }
00047 if (ff_pnm_decode_header(avctx, &pnmctx) < 0) {
00048 if (pnmctx.bytestream < pnmctx.bytestream_end) {
00049 if (pc->index) {
00050 pc->index = 0;
00051 } else {
00052 buf++;
00053 buf_size--;
00054 }
00055 goto retry;
00056 }
00057 #if 0
00058 if (pc->index && pc->index * 2 + FF_INPUT_BUFFER_PADDING_SIZE < pc->buffer_size && buf_size > pc->index) {
00059 memcpy(pc->buffer + pc->index, buf, pc->index);
00060 pc->index += pc->index;
00061 buf += pc->index;
00062 buf_size -= pc->index;
00063 goto retry;
00064 }
00065 #endif
00066 next = END_NOT_FOUND;
00067 } else {
00068 next = pnmctx.bytestream - pnmctx.bytestream_start
00069 + avpicture_get_size(avctx->pix_fmt, avctx->width, avctx->height);
00070 if (pnmctx.bytestream_start != buf)
00071 next -= pc->index;
00072 if (next > buf_size)
00073 next = END_NOT_FOUND;
00074 }
00075
00076 if (ff_combine_frame(pc, next, &buf, &buf_size) < 0) {
00077 *poutbuf = NULL;
00078 *poutbuf_size = 0;
00079 return buf_size;
00080 }
00081 *poutbuf = buf;
00082 *poutbuf_size = buf_size;
00083 return next;
00084 }
00085
00086 AVCodecParser ff_pnm_parser = {
00087 .codec_ids = { CODEC_ID_PGM, CODEC_ID_PGMYUV, CODEC_ID_PPM,
00088 CODEC_ID_PBM, CODEC_ID_PAM },
00089 .priv_data_size = sizeof(ParseContext),
00090 .parser_parse = pnm_parse,
00091 .parser_close = ff_parse_close,
00092 };