On Sat, 25 Mar 2017 12:28:26 +0100
wm4 <nfx...@googlemail.com> wrote:
> The old "API" that signaled rotation as a metadata value has been
> replaced by DISPLAYMATRIX side data quite a while ago.
>
> There is no reason to make muxers/demuxers/API users support both. In
> addition, the metadata API is dangerous, as user tags could "leak" into
> it, creating unintended features or bugs.
>
> ffmpeg CLI has to be updated to use the new API. In particular, we must
> not allow to leak the "rotate" tag into the muxer. Some muxers will
> catch this properly (like mov), but others (like mkv) can add it as
> generic tag. Note applications, which use libavformat and assume the
> old rotate API, will interpret such "rotate" user tags as rotate
> metadata (which it is not), and incorrectly rotate the video.
>
> The ffmpeg/ffplay tools drop the use of the old API for muxing and
> demuxing, as all muxers/demuxers support the new API. This will mean
> that the tools will not mistakenly interpret per-track "rotate" user
> tags as rotate metadata. It will _not_ be treated as regression.
>
> Unfortunately, hacks have been added, that allow the user to override
> rotation by setting metadata explicitly, e.g. via
>
> -metadata:s:v:0 rotate=0
>
> See references to trac #4560. fate-filter-meta-4560-rotate0 tests this.
> It's easier to adjust the hack for supporting it than arguing for its
> removal, so ffmpeg CLI now explicitly catches this case, and essentially
> replaces the "rotate" value with a display matrix side data. (It would
> be easier for both user and implementation to create an explicit option
> for rotation.)
>
> When the code under FF_API_OLD_ROTATE_API is disabled, one FATE
> reference file has to be updated (because "rotate" is not exported
> anymore).
> ---
> Not sure what happened - probably removed some redundant code and failed
> to retest properly. Maybe now?
> ---
> cmdutils.c | 10 +---------
> ffmpeg.c | 41 ++++++++++++++++++++++++++++++++++++-----
> ffmpeg.h | 1 +
> ffmpeg_opt.c | 12 ++++++++----
> libavformat/mov.c | 2 ++
> libavformat/movenc.c | 4 ++++
> libavformat/version.h | 3 +++
> 7 files changed, 55 insertions(+), 18 deletions(-)
>
> diff --git a/cmdutils.c b/cmdutils.c
> index 2373dbf841..3d428f3eea 100644
> --- a/cmdutils.c
> +++ b/cmdutils.c
> @@ -2097,18 +2097,10 @@ void *grow_array(void *array, int elem_size, int
> *size, int new_size)
>
> double get_rotation(AVStream *st)
> {
> - AVDictionaryEntry *rotate_tag = av_dict_get(st->metadata, "rotate",
> NULL, 0);
> uint8_t* displaymatrix = av_stream_get_side_data(st,
>
> AV_PKT_DATA_DISPLAYMATRIX, NULL);
> double theta = 0;
> -
> - if (rotate_tag && *rotate_tag->value && strcmp(rotate_tag->value, "0")) {
> - char *tail;
> - theta = av_strtod(rotate_tag->value, &tail);
> - if (*tail)
> - theta = 0;
> - }
> - if (displaymatrix && !theta)
> + if (displaymatrix)
> theta = -av_display_rotation_get((int32_t*) displaymatrix);
>
> theta -= 360*floor(theta/360 + 0.9/360);
> diff --git a/ffmpeg.c b/ffmpeg.c
> index 532db80e0b..90441224f9 100644
> --- a/ffmpeg.c
> +++ b/ffmpeg.c
> @@ -50,6 +50,7 @@
> #include "libavutil/internal.h"
> #include "libavutil/intreadwrite.h"
> #include "libavutil/dict.h"
> +#include "libavutil/display.h"
> #include "libavutil/mathematics.h"
> #include "libavutil/pixdesc.h"
> #include "libavutil/avstring.h"
> @@ -3067,9 +3068,6 @@ static int init_output_stream_streamcopy(OutputStream
> *ost)
> const AVPacketSideData *sd_src = &ist->st->side_data[i];
> AVPacketSideData *sd_dst =
> &ost->st->side_data[ost->st->nb_side_data];
>
> - if (ost->rotate_overridden && sd_src->type ==
> AV_PKT_DATA_DISPLAYMATRIX)
> - continue;
> -
> sd_dst->data = av_malloc(sd_src->size);
> if (!sd_dst->data)
> return AVERROR(ENOMEM);
> @@ -3080,6 +3078,13 @@ static int init_output_stream_streamcopy(OutputStream
> *ost)
> }
> }
>
> + if (ost->rotate_overridden) {
> + uint8_t *sd = av_stream_new_side_data(ost->st,
> AV_PKT_DATA_DISPLAYMATRIX,
> + sizeof(int32_t) * 9);
> + if (sd)
> + av_display_rotation_set((int32_t *)sd,
> -ost->rotate_override_value);
> + }
> +
> ost->parser = av_parser_init(par_dst->codec_id);
> ost->parser_avctx = avcodec_alloc_context3(NULL);
> if (!ost->parser_avctx)
> @@ -3233,6 +3238,11 @@ static int init_output_stream_encode(OutputStream *ost)
>
> set_encoder_id(output_files[ost->file_index], ost);
>
> + // Muxers use AV_PKT_DATA_DISPLAYMATRIX to signal rotation. On the other
> + // hand, the legacy API makes demuxers set "rotate" metadata entries,
> + // which have to be filtered out to prevent leaking them to output files.
> + av_dict_set(&ost->st->metadata, "rotate", NULL, 0);
> +
> if (ist) {
> ost->st->disposition = ist->st->disposition;
>
> @@ -3470,6 +3480,26 @@ static int init_output_stream(OutputStream *ost, char
> *error, int error_len)
> }
> }
>
> + /*
> + * Add global input side data. For now this is naive, and copies it
> + * from the input stream's global side data. All side data should
> + * really be funneled over AVFrame and libavfilter, then added back
> to
> + * packet side data, and then potentially using the first packet for
> + * global side data.
> + */
> + if (ist) {
> + int i;
> + for (i = 0; i < ist->st->nb_side_data; i++) {
> + AVPacketSideData *sd = &ist->st->side_data[i];
> + uint8_t *dst = av_stream_new_side_data(ost->st, sd->type,
> sd->size);
> + if (!dst)
> + return AVERROR(ENOMEM);
> + memcpy(dst, sd->data, sd->size);
> + if (ist->autorotate && sd->type == AV_PKT_DATA_DISPLAYMATRIX)
> + av_display_rotation_set((uint32_t *)dst, 0);
> + }
> + }
> +
> // copy timebase while removing common factors
> if (ost->st->time_base.num <= 0 || ost->st->time_base.den <= 0)
> ost->st->time_base = av_add_q(ost->enc_ctx->time_base,
> (AVRational){0, 1});
> @@ -4266,9 +4296,10 @@ static int process_input(int file_index)
> AVPacketSideData *src_sd = &ist->st->side_data[i];
> uint8_t *dst_data;
>
> - if (av_packet_get_side_data(&pkt, src_sd->type, NULL))
> + if (src_sd->type == AV_PKT_DATA_DISPLAYMATRIX)
> continue;
> - if (ist->autorotate && src_sd->type == AV_PKT_DATA_DISPLAYMATRIX)
> +
> + if (av_packet_get_side_data(&pkt, src_sd->type, NULL))
> continue;
>
> dst_data = av_packet_new_side_data(&pkt, src_sd->type,
> src_sd->size);
> diff --git a/ffmpeg.h b/ffmpeg.h
> index c3ed6ced78..4d0456c1fb 100644
> --- a/ffmpeg.h
> +++ b/ffmpeg.h
> @@ -475,6 +475,7 @@ typedef struct OutputStream {
> int force_fps;
> int top_field_first;
> int rotate_overridden;
> + double rotate_override_value;
>
> AVRational frame_aspect_ratio;
>
> diff --git a/ffmpeg_opt.c b/ffmpeg_opt.c
> index fc885dfac3..ffe1abdb38 100644
> --- a/ffmpeg_opt.c
> +++ b/ffmpeg_opt.c
> @@ -2549,8 +2549,6 @@ loop_end:
> av_dict_copy(&output_streams[i]->st->metadata,
> ist->st->metadata, AV_DICT_DONT_OVERWRITE);
> if (!output_streams[i]->stream_copy) {
> av_dict_set(&output_streams[i]->st->metadata, "encoder",
> NULL, 0);
> - if (ist->autorotate)
> - av_dict_set(&output_streams[i]->st->metadata, "rotate",
> NULL, 0);
> }
> }
>
> @@ -2640,9 +2638,15 @@ loop_end:
> for (j = 0; j < oc->nb_streams; j++) {
> ost = output_streams[nb_output_streams - oc->nb_streams + j];
> if ((ret = check_stream_specifier(oc, oc->streams[j],
> stream_spec)) > 0) {
> - av_dict_set(&oc->streams[j]->metadata,
> o->metadata[i].u.str, *val ? val : NULL, 0);
> if (!strcmp(o->metadata[i].u.str, "rotate")) {
> - ost->rotate_overridden = 1;
> + char *tail;
> + double theta = av_strtod(val, &tail);
> + if (!*tail) {
> + ost->rotate_overridden = 1;
> + ost->rotate_override_value = theta;
> + }
> + } else {
> + av_dict_set(&oc->streams[j]->metadata,
> o->metadata[i].u.str, *val ? val : NULL, 0);
> }
> } else if (ret < 0)
> exit_program(1);
> diff --git a/libavformat/mov.c b/libavformat/mov.c
> index 3754346f9e..a00c53a676 100644
> --- a/libavformat/mov.c
> +++ b/libavformat/mov.c
> @@ -4030,6 +4030,7 @@ static int mov_read_tkhd(MOVContext *c, AVIOContext
> *pb, MOVAtom atom)
> for (j = 0; j < 3; j++)
> sc->display_matrix[i * 3 + j] = res_display_matrix[i][j];
>
> +#if FF_API_OLD_ROTATE_API
> rotate = av_display_rotation_get(sc->display_matrix);
> if (!isnan(rotate)) {
> char rotate_buf[64];
> @@ -4039,6 +4040,7 @@ static int mov_read_tkhd(MOVContext *c, AVIOContext
> *pb, MOVAtom atom)
> snprintf(rotate_buf, sizeof(rotate_buf), "%g", rotate);
> av_dict_set(&st->metadata, "rotate", rotate_buf, 0);
> }
> +#endif
> }
>
> // transform the display width/height according to the matrix
> diff --git a/libavformat/movenc.c b/libavformat/movenc.c
> index 11b26708ae..3b4e3b519c 100644
> --- a/libavformat/movenc.c
> +++ b/libavformat/movenc.c
> @@ -2496,19 +2496,23 @@ static int mov_write_tkhd_tag(AVIOContext *pb,
> MOVMuxContext *mov,
> avio_wb16(pb, 0); /* reserved */
>
> /* Matrix structure */
> +#if FF_API_OLD_ROTATE_API
> if (st && st->metadata) {
> AVDictionaryEntry *rot = av_dict_get(st->metadata, "rotate", NULL,
> 0);
> rotation = (rot && rot->value) ? atoi(rot->value) : 0;
> }
> +#endif
> if (display_matrix) {
> for (i = 0; i < 9; i++)
> avio_wb32(pb, display_matrix[i]);
> +#if FF_API_OLD_ROTATE_API
> } else if (rotation == 90) {
> write_matrix(pb, 0, 1, -1, 0, track->par->height, 0);
> } else if (rotation == 180) {
> write_matrix(pb, -1, 0, 0, -1, track->par->width,
> track->par->height);
> } else if (rotation == 270) {
> write_matrix(pb, 0, -1, 1, 0, 0, track->par->width);
> +#endif
> } else {
> write_matrix(pb, 1, 0, 0, 1, 0, 0);
> }
> diff --git a/libavformat/version.h b/libavformat/version.h
> index dd4c680803..7b92255bea 100644
> --- a/libavformat/version.h
> +++ b/libavformat/version.h
> @@ -94,6 +94,9 @@
> #ifndef FF_API_LAVF_KEEPSIDE_FLAG
> #define FF_API_LAVF_KEEPSIDE_FLAG (LIBAVFORMAT_VERSION_MAJOR < 58)
> #endif
> +#ifndef FF_API_OLD_ROTATE_API
> +#define FF_API_OLD_ROTATE_API (LIBAVFORMAT_VERSION_MAJOR < 58)
> +#endif
>
>
> #ifndef FF_API_R_FRAME_RATE
Pushed, with added version bump + APIchanges entry. Thanks for review.
_______________________________________________
ffmpeg-devel mailing list
ffmpeg-devel@ffmpeg.org
http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
